Art. XLIII.—On the Lichenographia of New Zealand. By Charles Knight, F.R.C.S. [Read before the Wellington Philosophical Society, 28th February, 1883.] Plates XXXV.–XXXVIII. In continuing my papers on the Lichenographia of New Zealand, I wish to make the following remarks:— In respect of the Arthoniœ. The leading characters of this genus, as given by Leighton in 3rd. ed. of Lichen Flora, are:—“Asci pyriform in excavations of the sub-gelatinous hymenium; paraphyses none.” The term “excavations” is not a happy one, but let that pass. Nylander seems to avoid committing himself to an unqualified statement of character, and instead of “paraphyses none,” limits himself merely to the terms “para-physibus discretis nullis.” In reference to the above, I have already, in a paper on the lichens of New South Wales, called attention to the remark of Professor J. Müller, of Geneva (Flora, 11th April, 1879), where he states that paraphyses are always present in the Arthoniœ. This assertion of Müller needs qualification. In those Arthoniœ where the lamina sporigera is said to be grumose or homogeno-grumose, there exists in most cases no trace whatever of paraphyses or of stratification,—the structure is confused, cellular, or even granular. In others, where the lamina sporigera is said to be floccose, the structure is really clathrato-ramose, and is mostly condensed and rendered columnar in appearance by the pressure of the growing asci, as is seen in A. globulosœformis, Hepp, A. lurida, Ach., A. kempelhuberi, Mass., etc. Again in others distinct filaments can be traced, knit together in a more or less open network, as in A. gregaria, Ach., A. swartziana, Ach., A. oleandri, etc., and also as in most of the species of

Arthonia described in the present paper, with the exception of A. aspera (n. sp.), in which the lamina sporigera is more or less carbonized and degraded. In respect of the Pertusariœ importance is always attached to the extraordinary thickness of the sporal envelope, which often consists of three or more laminæ; and this characteristic, when the paraphyses are implexoramose, is of the highest importance. Indeed, the presence of implexoramose paraphyses has induced Professor Müller to transfer several Lecanorœ to Pertusaria. In a paper on the lichens of New South Wales (Linn. Trans. Botany, second series, vol. 2) I called attention to Professor Müller's remarks (Flora, 1879, No. 39, p. 484) in which he advocates these transfers, and I noticed that, in my opinion, besides L. parella and L. pallescens, there are other species liable to similar removal; for instance, L. verrucosa, and L. calcarea. Hepp, together with Nylander and Th. Fries, has placed Lecanora bryontha, Ach., with the Pertusariœ, an arrangement amply supported by the great thickness of the parietes of the solitary spores and the implexo-ramose paraphyses. It may be added that the presence of intricate ramose paraphyses with thick double sporal envelopes renders it necessary that Lecanora gemmifera, Th. Fries, should also be transferred to Pertusaria. P. fumosa (n. sp.) of the present paper has a thin sporal envelope. I have read with some interest in the Flora (1882, p. 458) Dr. Nylander's objections to break up a large genus of closely-allied species and dispose of them in several genera. We all agree with Ray,—“Methodum intelligo naturæ convenientem quæ nec alienas species conjungit, nec cognitas separat.” But it seems to be contended by Dr. Nylander that cognate species, however numerous they may be, ought not to be separated into genera and that no limiting number of species can be assigned to a genus. Certainly there is no reason why we should fix upon an arbitrary limiting number, which it would be improper to exceed; although, on the other hand, it may be desirable that genera should not be overburdened with species. One of the objects of classification is, that the generic name, like an algebraic formula, should be the symbol of certain characteristics of all the species included in the genus and these are stored in our memory. To take an instance. There are not much less than 500 species at present arranged under Lecidea, a genus which is limited by a small number of characters. Is it not a real disadvantage to the progress of a science that the generic name in this instance conveys to the mind so little of the nature and organization of any one of the 500 species. On the other hand, if we break up the Lecideœ into several genera and group the new genera in

natural sequence under one tribe or subtribe, the few characters which at present define the genus would be sufficient for the higher group, in accordance with the law enforced by Jussieu, that the larger the group the fewer the characters by which it is limited. What reasonable objection can be urged to the proposal. We should outrage no natural alliance of the species. While the advantage would consist in this, that the name of each lichen would carry with it not only the tribal characters but also its distinguishing generic characteristics, and would thus secure to the student one of the leading objects of a natural classification. It is urged that to scatter cognate species amongst a number of genera would be an offence against the harmony that exists in nature; but if so, and we are to be governed by mere prudery, no division of species could be admitted, seeing that, as Ray asserted and Linnæus copied, “Natura non facit saltus.” Indeed, there is no scheme of classification which is not liable to the objection that between two closely-allied genera there will always be one or more species which can be placed in either of the two; and, as Lindley observes in “The Vegetable Kingdom,”—“it cannot be of any possible consequence whether an intermediate or frontier plant be assigned to one group or another and convenience alone should be considered in such a matter, * * * All the groups into which plants are thrown are, in one sense, artificial, inasmuch as Nature recognizes no such groups. Nevertheless, consisting in all cases of species very closely-allied in nature, they are in another sense natural. But as the classes, subclasses, alliances, natural orders and genera of botanists have no real existence in nature, it follows they have no fixed limit and consequently it is impossible to define them.” That differences exist among the Lecideœ as now constituted sufficient for the purpose of arranging the species under several genera is certain from the success which appears to have attended the labours of Massolonga and others. Nylander himself has arranged them in sections. As to the questionable value of Massolonga's scheme, I do not at present wish to make any remarks, or to criticize Nylander's sectional arrangement. 1. Bœomyces novœ-zealandiœ, n. sp. Thallus crustaceus tenuissimus sordide luteolus, madefactus albovirescens, effusus pulverulens (microscopi area granula gonima obsita). Apothecia discoidea peltata, in centro peranguste adnata (diam. circa 2 mm.) madefacta albo-incarnata et convexa, margine obsoleto, excipulo proprio incolorato arachnoideo-filamentoso (filis diam. 0.001 mm.), paraphysibus tenuissimis densatis paucis apice laxis nonnihil ramosis. Sporæ in ascis cylindraceis angustissimis confertissimis uniseriales oblongo-subfusiformes incolores simplices, guttam unam magnam (evanescentem glycerinâ) centralem continentes, longit. 0.017 mm., crassit. 0.006 mm.

Lichenes.

Obs.—B. roseus (Sch. No. 31) thallo granuloso, sporis fusiformibus leviter curvatis (long. 0.015, crass. 0.0025 mm.) luteolis. B. byssoides (Schær. No. 32) hymenio fusco, sporis ellipsoideis long. 0.01 mm., crass. 0.004 mm. 2. Thelotrema circumscriptum, n. sp. Thallus ex ochraceo pallido-fuscus lævis subnitiusculus tenuis continuus linea fusca determinatus, verrucis apotheciorum hemisphæricis (diam. 0.5 ad 1 mm.) prominulis, ostiolo simplici. Apothecia immersa excipulo proprio laterali dilute fusco instructa, matrice enata, madefacto epithecio in sectione multo dilato, paraphysibus distinctis apice dilute coloratis. Sporæ subclaviformes interdum oblongæ hyalinæ 6–12-septatæ, long. 0.02 ad 0.035 mm., crassit. 0.005 mm. Ad cortices arborum. 3. Thelotrema farinaceum, n. sp. Thallus albus cartilagineus nitidus continuus, verrucis apotheciorum globosis confertis. Apothecia primum clausa tandem late aperta, disco dilute colorato albo-pruinoso, margine albo elevato farinaceo, paraphysibus subtilissimis subramosis. Sporæ in ascis crebris monosporis oblongoclavatæ circiter 14-septatæ, longit. 0.14 mm., crassit. 0.04 mm. Ad arborum cortices. 4. Pertusaria leucodes, n. sp. Thallus albus passim rimosus, verrucis apotheciorum convexis v. hemisphæricis concoloribus, ostiolo primitus minuto mox in pseudo-discum nunc planum nunc urceolatum (interdum cavatum) confluentibus. Apothecia 1–3 in quavis verruca, excipulo proprio nullo, hymenio thallo enato, paraphysibus adglutinatis clathratim-ramosis. Sporæ 2, 4, 8næ, in iisdem apotheciis, ellipsoideæ simplices, pluries limbatæ, longit. 0.05 mm., crassit. 0.02 mm. Ad arborum cortices. 5. Pertusaria fumosa, n. sp. Thallus fumoso-nigricans intus albus tuberculosus, tuberculis apotheciorum parvis globosis albescentibus mox hiantibus, epithecium urceolatum nigrescens denudantibus, margine elevato nonnihil subtumido irregulari, excipulo proprio nullo, hymenio strato gonimico oriundo, paraphysibus adglutinatis obscure ramosis. Sporæ in ascis clavatis ovoideæ simplices angusté limbatæ luteolæ, longit. 0.025 mm., crassit. 0.012. Ad arborum cortices. 6. Phlyctis stromaphora, n. sp. Thallus crassus albidus granulosus areolatus, areolis nonnihil conglobatis. Apothecia in stromatibus thallinis creberrimis rotundato-difformibus v. convexo-prominentibus v. planis inæqualibus immersa, plura in singulis

stromatibus, punctis minutis indicata inde plerumque pyreno-carpoidea, passim epitheciis tandem evolutis fuscis concavis sæpe confluentibus et tum varie oblongis, margine thallino elevato cinctis, madefactis thallum æquantibus; hymenium thalli strato crasso impositum, paraphysibus capillaribus non discretis apice fuscis non dilatis. Sporæ ellipsoideæ v. fusiformes nonnunquam cuneiformes 7–8-septatæ tandem flavescentes, longit. 0.057 mm., crassit. 0.013 mm. Ad arborum cortices. 7. Phlyctis cyrtospora, n. sp. Thallus cinereo-albidus tenuis lævis continuus, arefactus minutissime areolatus. Apothecia innata rotundato-difformia parva sparsa (solitaria v. aggregata), margine thallino crasso plano elevato, excipulo proprio nullo, paraphysibus bene discretis. Sporæ oblongo-fusiformes nonnunquam cuneiformes 7-septatæ luteolæ demum fuscentes curvatæ, longit. 0.085 mm., crassit. 0.018 mm. Ad arborum cortices. Obs.—Phlyctis oleosa, Stirt., “thallus areolato-diffractus, areolis concavis, sporæ incolores in thecis incrassatis una cum guttulis flavidis oleosis inclusæ” (Stirton). 8. Bacidia minutissima, n. sp. Thallus tenuis ex olivaceo fuscus continuus indeterminatus. Apothecia minutissima (diam. 0.2 mm.) innata convexa nigro-fusca nonnihil e thallo velata immarginata, hymenio (in sectione subtilissima) dilute fusco, strato subhymeniale fusco, excipulo proprio dilute fusco—texturâ radiatim dispositâ—paraphysibus adglutinatis gracilibus apice dilutis fuscis. Sporæ in ascis clavatis bacillares spiraliter curvatæ nonnihil rectæ circiter 9-septatæ incolores, longit. 0.043 mm., crassit. 0.003 mm. Ad arborum cortices. 9. Lecidea (Catillaria) clathrata, n. sp. Thallus cinereus v. dilutæ cinereo-viridescens subgranulosus continuus linea atra limitatus. Apothecia atro-fusca superficialia (diam. circ. 3 mm.) nonnullo margine thallode in parte instructa, disco pruinoso, margine proprio atro-fusco prominente nonnihil nitido, hypothecio incolori excipuli linea atra imposito, excipulo dilute ochraceo-fusco in summo atro et linea atra omnino circumscripto, paraphysibus adglutinatis subtilissimis (crassit. 0.001 mm.) clathrato-ramosis. Sporæ in ascis oblongis magnæ ovatæ plerumque incurviusculæ uniseptatæ (epispora crass. 0.005 mm.) incolores, longit. 0.06 mm., crassit. 0.03 mm. Ad arborum cortices. Obs.—Inter L. marginiflexam atque L. clathratam præcipua differentia in sporis illius oblongis et ascis monosporis, hujus sporis ovatis et 8nis est

posita. L. grossa, excipulo omnino carbonizato. L. versicolor, v. tuberculosa, et L. taitensis excipuli structura radiante. L. grossa, versicolor, taitensis, sporis multo minoribus quam in L. clathrata. 10. Lecidea cinnabaroides, n. sp. Thallus sordide testaceus effusus nonnihil leprosus tenuissimus. Apothecia rubra sparsa, margine concolore crassiusculo prominente, excipulo e guttis oleaceis hyalinis alius minutis alius sat grandibus formato, textura non radiatim disposita, a lateribus et basi per lineam tenuem aurantiacam contento, paraphysibus distinctis apice coloratis ovato-dilatis. Sporæ in ascis clavatis simplices luteolæ v. incolores ellipsoideæ, longit. 0.015 mm., crassit. 0.007 mm. Ad arborum cortices. Obs.—L. cinnabaroides, Nyl., in litt. 11. Arthonia (Coniangium) stictaria, Nyl. Thallus nullus. Apothecia atra innata rotundata ambitu applanata in centro convexa, hymenio tenui (crass. 0.035 mm.) pseudo-excipulo e matrice vitiata constante, lamina sporigera laxissime clathrata, hypothecio tenui grumoso in marginem se explicato. Sporæ in ascis pyriformibus minutæ obovatæ incolores 1-septatæ, cellula superiore ampliore, long. 0.009 mm., crass. 0.0035 mm. Ad Stictam auratam parasitica. 12. Arthonia (Coniangium) conspicua, Nyl. Thallus sordide albus tenuissimus (v. nullus) continuus. Apothecia hypoplæodes sparsa rubricoso-fusca nuda rotundata v. difformia aspera, madefacta convexa (diam. circiter 1 mm.), intus luteo-fusca, lamina sporigera perfecto clathrato-ramosa. Sporæ in ascis globosis oblongo-ovoideæ 1-septatæ (cellula superiore vix ampliore) dilute luteo-fuscæ tandem fuscæ, emortuæ atro-fuscæ, longit. 0.025 ad 0.032 mm., crassit. 0.01 ad 0.012 mm. Ad arborum cortices. Obs.—Ab A. lurida, Ach., et A. vinosa, Leight., differt sporis duplo majoribus. Syn. Myriangium inconspicuum, Bab. (“Flora New Zealand,” p. 310.) 13. Arthonia aspera, n. sp. Thallus albidus v. albido-cinerascens, plagulas parvas formans, tenuissimus lævis continuus. Apothecia hypoplæodes adnata aspera atra rotundato-difformia parva (latit. circiter 0.5 mm.) intus fusca excipulo destituta hymenio nullo, lamina sporigera floccosa plus minus carbonizata. Sporæ in ascis pyriformibus cuneato-oblongæ 6-loculares, loculo supremo vix ampliore, fuscæ emortuæ atro-fuscæ, long. .017, crassit. .006 mm. Ad cortices.

14. Arthonia lecideoides n. sp. Thallus uniformis lævis v. pulverulento-furfuraceus (passim byssoideo-furfuraceus) olivaceus, gonidiis crebris. Apothecia pseudo-lecidina hypoplæodes rotundato-difformia plana non-nihil subconvexa atra adnata immarginata (diam. circiter 1 mm.) hymenio fusco, lamina sporigera floccosa (vere subtilissime clathratim ramosa), basi laminæ sporigeræ et matrice plus minus carbonizatis, crassis. Asci pyriformes inter laminas sporigeras condensatas oriundi. Sporæ nymphæformes ex hyalino fuscidulæ, emortuæ fuscæ, 5-cellulæ, cellula extrema ampliore, longit. .023, crassit. .008 mm. Ad cortices. 15. Arthonia lirellœformis, n. sp. Thallus e lilacino cinerascens tennis lævis continuus per lineam fuscam limitatus. Apothecia hypoplæodes (matrice immutata) fusca lirellæformia oblonga v. elongata simplicia v. ramosa plerumque flexuosa undique attenuata innata ambitu cinereo-pulverulenta, hymenii lateri carbonizato, lamina sporigera clathrata et tanquam ab ascis compressa epithecio atrofusco. Sporæ in ascis pyriformibus obtuse cuneato-oblongæ tandem fuscidulæ 4-septatæ, cellula suprema ampliore, longit. 0.02 mm., crassit. 0.008 mm. Ad cortices arborum. 16. Arthonia pellucida, n. sp. Thallus e cinereo albus tennissimus lævis continuus. Apothecia hypoplæodes (matrice immutata) atro-fusca depressiuscula lobato-difformia sæpe inter se juneta, ambitu a thallo plus minus velata intus pellucida, pseudoexcipulo omnino destituta, lamina sporigera laxissime clathrata. Sporæ in ascis globosis cuneato-oblongæ hyalinæ tandem fuscidulæ 5-septatæ, cellula superiore ampliore ceteris plerumque longitudionalibus divisis, longit. 0.02 mm., crassit. 0.008 mm. Ad arborum cortices. Obs.—Affinis est A. lirellœformi et vix differt nisi pseudo-excipulo omnino egente et sporæ cellulis longitudionalibus divisis; fortasse tamen haud species est distincta. 17. Arthonia (Lecanactis) tenuissima. Thallus nullus v. macula minuta albida indicatus. Apothecia hypoplæodes (matrice immutata) atra maculæformia intus mox fusca v. atra, hymenio tenui (crass. 0.06 mm.), ambitu evanescente, lamina sporigera lasissime clathrata. Asci fusiformi-ellipsoidei creberrimi (long. 0.046 mm.) Sporæ naviculares hyalinæ mox fuscescentes emortuæ atro-fuscæ 5-septatæ, cellulis mediis paulo amplioribus, longit. 0.014 mm., crassit. 0.005 mm. Ad arborum cortices.

Lichenes.

Lichenes.

18. Arthonia (Lecanactis) verruculosa, n. sp. Thallus sordide cinereus plus minus rimosus in agellos a hypothallo (e matrice carbonizata constante) denudato metatus. Apothecia hypoplæodes fusco-atra rotundato-difformia plana singulis thalli areolis verruculisve innata, verruculis vix elevatis, hymenio tenui dilute fusco, pseudoexcipulo e matrice carbonizata constante, lamina sporigera obscura clathratim ramosa. Sporæ in ascis clavatis crebris emortuis fuscis cymbiformes 3-septatæ hyalinæ, long. 0.014 mm., crassit. 0.005 mm. Ad arborum cortices. 19. Arthonia (Arthothelium) suffusa, n. sp. Thallus squamulis albidis conglutinatis minutissimis constans, subtiliter areolatus, in agellos a hypothallo nigro denudato metatus. Apothecia hypoplæodes minuta crebra nigricantia prominula rotundata nonnihil e thallo suffusa (latit. circiter .5 mm. v. minora) a thallo interdum coronata, excipulo omnino destituta, lamina sporigera obscure clathrata. Sporæ in ascis ellipsoideo-oblongis ovatæ v. oblongæ demum fuscæ, seriebus 7–9 transversim loculosæ, loculis plerumque 3 in quavis seriebus, longit. .033 mm., crassit. .028 mm. Matrix non mutatur. Obs.—Prope Arthoniam abnormem, Ach., et A. anastomosantem; differt vero sporis majoribus. Ad cortices. 20. Arthonia (Arthothelium) spadicea, n. sp. Thallus cinereo-albus uniformis tenuis lævis linea nigra limitatus. Apothecia hypoplæodes spadicea v. ochreo-fusca innata plana rotundato-difformia v. irregulariter elongata (latit. circiter 1 mm.) a thallo non coronata, excipulo omnino destituta, hypothecio nullo, lamina sporigera floccosa—obscure clathratim ramosa. Asci pauci ventricoso-globosi (latit. 0.5 mm.) Sporæ ovatæ v. oblongæ fuscæ, seriebus circa 10 transversim loculosæ, plerumque 5 in quavis seriebus, longit. .04, crassit. .018 mm. Matrix non mutatur. Ad cortices. Obs.—Prope Arthoniam xanthocarpam, Nyl.; sed differt sporis coloratis minoribus loculisque majoribus, et thallo continuo. 21. Stigmatidium confluens, n. sp. Thallus ex albo cinereus cartilagineus continuus, protuberantibus thallinis apotheciorum vix ullis subconvexis confluentibus, ostiola minutissima. Apothecia orbicularia immersa excipulo proprio crasso dilute luteo-colorato integro instructa, hymenio madefacto latit. circ. 0.3 mm., paraphysibus distinctis apice non coloratis. Sporæ in ascis cylindraceis oblongæ 4-cellulæ hyalinæ nonnihil luteolæ, longit. 0.02 mm., crassit. 0.011 mm. Ad arborum cortices.

22. Fissurina monospora, n. sp. Thallus cinereo-albus rugosus, rugis apothecia rimiformia includentibus. Apothecia immersa conferta flexuosa brevia intus incoloria, marginibus thallinis conniventibus crassis tumidis elevatis, excipulo proprio nullo, paraphysibus adglutinatis gracilibus cellularibus (cellulis longit. 0.01 mm.) Asci perpauci monospori, parietibus tenuissimis. Sporæ ovatoellipsoideæ lutea minute murali-divisæ, longit. 0.18 mm., crassit. 0.08 mm. Ad arborum cortices. 23. Fissurina cyrtospora, n. sp. Thallus e luteolo albidus tenuis lævis continuus, in gonidiis veris glaucescentibus consistens. Apothecia linearia (latit. 0.3 mm.) elongata furcato-divisa flexuosa, marginibus thallinis concoloribus conniventibus tumidis, excipulo proprio nullo, hymenio matrice imposito, lamina sporigera granulosa (paraphysibus nullis !). Sporæ in ascis ventrico-clavatis oblongæ plus minus curvatæ simplices, longit. 0.026 mm., crassit. 0.007 mm. Ad arborum cortices. 24. Ascidium fusiforme, n. sp. Thallus e viridi cinereus tenuis leprosus, verrucis apotheciorum convexis v. subhemisphæricis pallido-fuscis circa ostiola minutissima pallidis vix prominulis. Apothecia excipulo proprio globoso integro pallido-luteofusco instructa, paraphysibus subtiliter capillaribus bene distinctis. Sporæ in ascis cylindraceis 4–8næ acute fusiformes 7–9-septatæ hyalinæ, longit. 0.09 mm., crassit. 0.02 mm. Ad cortices arborum. Obs.—Affine V. desquamescenti, Fée (Leight. Lich. Ceyl.), a qua differt præcipue sporis prope duplo majoribus et verrucis circiter triplo majoribus. Excipulum (= perithecium) V. desquamescentis integrum quod ad exemplum Thwaitsii in meo herbario attinet,—“Perithecium dimidiatum.” (Leight. Trans. Linn. Soc., vol. xxvii., p. 183.) 25. Ascidium attenuatum, n. sp. Thallus albescens tenuis continuus, verrucis apotheciorum convexomastoideis concoloribus, ostiolo latiore. Apothecia partim in matrice immersa, excipulo depresso-globoso tenui pallido-fusco, epithecio colorato madefacto in pseudo-discum confluente, paraphysibus subtiliter capillaribus bene discretis. Sporæ in ascis 1–3 sporis fusiformes utrimque attenuatæ 25–30-septatæ primum hyalinæ mox fuscæ tandem atro-fuscæ, longit. 0.113 mm., crassit. 0.021 mm. Ad cortices. Obs.—Affine est Ascidio domingensi, Fée.

26. Ascidium manosporum, n. sp. Thallus albus v. sordide albus effusus tenuis, verrucis apotheciorum convexis concoloribus v. pallido-fuscis, ostiola minutissima prominula. Apothecia excipulo proprio globoso integro tenui fusco instructa, hymenio tandem atro-fusco (in lamina subtilissima fusco); paraphysibus capillaribus bene distinctis. Sporæ in ascis monosporis fusiformes v. elongato-cylindraceæ tandem fuscæ murali-divisæ—seriebus loculorum transversis 20–30 in quavis serie 2–8 loculis in medio et 3–1 versus apicem utrumque, longit. 0.1 ad 0.13 mm., crassit 0.02 ad 0.03 mm. Ad cortices. Obs.—Var. α. Excipulum et hymenium pallida. 27. Verrucaria (Leptorhaphis) macrocyrtospora, n. sp. Thallus obscurus macula pallido-flavescente indicatus (vix matricem colorans) v. nullus, verruculis apotheciorum minutis (basi latit. circa 0.8 mm.) convexis. Apothecia orbicularia primitus immersa, excipulo proprio atro integro mox supra denudato—tum margine thallode tumidulo—hymenio dilute fusco, paraphysibus capillaribus perplexis. Sporæ in ascis cylindraceis (long. 1.3 mm.) aciculares utrimque acutatæ hyalinæ in arcum constanter plus minus curvatæ 13-septatæ v. ultra, longit. 0.11, crass. 0.003 mm. Ad arborum cortices. Obs.—Verr. beloniza, Stirt. Sporæ rectæ, septa non visa. 28. Verrucaria submargacea, n. sp. Thallus olivaceo-fuliginosus tenuissimus contiguus lævigatus determinatus, gonidiis veris ubique confertis. Apothecia nigra minuta (diam. 0.3 mm.) hemisphærica protuberantia a thallo leviter obtecta, excipulo dimidiato atro apice poro minutissimo instructo, paraphysibus nullis. Sporæ in ascis clavatis simplices dacryoideæ incolores, longit. 0.023, crassit. 0.01 mm. Ad saxa. Obs.—Persimilis V. œthiobolœ præcipue sporis dacryoideis sed differens sporis majoribus. 29. Verrucaria (Polyblastia) trachyspora, n. sp. Thallus fuscus tenuissimus continuus. Apothecia hemisphærica minuta dimidiata atra ad basim immersa, ostiolo depresso minutissimo madefacto prominente ambitu albescente, paraphysibus distinctis ramosis. Sporæ in ascis claviformibus nonnullis cylindraceis ovatæ murali- v. ruderiformidivisæ, cellulis subpaucis irregularibus, hyalinæ incolores interdum luteolæ, longit. 0.018, crassit. 0.01 mm. Ad lapides. Obs.—P. tichospora, Knight (Trans. Linn. Soc., vol. ii, p. 37). Thallus cinerascens, sporæ minores.

30. Verrucaria (Pyrenula) arthoniza, n. sp. Thallus ochraceus v. pallido-ochraceus tenuis areolatus, verrucis apotheciorum minutis (basi latit. circ. 0.5 mm.) hemisphæricis v. convexis. Apothecia orbicularia primitus immersa, excipulo proprio atro crasso integro mox supra denudato—tum arthonoidea et margine thallode tumidulo—paraphysibus distinctis. Sporæ in ascis cylindraceis, ellipsoideæ normaliter loculos 4 transversos lentiformes offerentes, hyalinæ tandem fuscescentes, longit. 0.015, crassit. 0.006 mm. Ad arborum cortices. 31. Verrucaria (Acrocordia) subatomaria, n. sp. Thallus obscurus v. nullus. Matrix non mutatur. Apothecia mintissima orbicularia (diam. 0.2 mm.) in matrice subimmersa, excipulo proprio integro atro-fusco, ostiolo minuto nonnihil hiante, hymenio pallido-fusco paraphysibus reticulato-capillaribus. Sporæ in ascis elongato-pyriformibus oblongæ 1-septatæ incolores hyalinæ, longit. 0.017, crassit. 0.007 mm. Ad cortices. Obs.—V. subatomaria, Nyl., in litt. Dr. Nylander's name is adopted. It will be seen, however, that the entire proper excipulum and hyaline colourless spores separate this species so widely from V. atomaria, DC., as to render the prefix of “sub” somewhat misleading. 32. Verrucaria (Segestria) metabletica, n. sp. Thallus sordide cinereus tenuis continuus (matrice reticulato-rugosa) granulas gonimas virides in nodulis magnis continens. Apothecia madefacta adnata atra minuta (diam. 0.2 mm.) hemisphærica, excipulo dimidiato, ostiolo pallido minutissimo v. nullo, paraphysibus distinctis. Sporæ in ascis cylindraceis fusiformes incolores 3–7-septatæ, longit. 0.02, crassit. 0.005 mm. Ad arborum cortices. Obs.—Var. α. Thallus albescens, sporæ 7-cellulæ, cellulis medio majoribus. 33. Verrucaria (Thelidium) suffusa, n. sp. Thallus cinereus tenuis effusus a linea fusca limitatus. Apothecia minuta (diam. 0.3 mm.) hemisphærica thallo leviter obtecta, excipulo atro crasso dimidiato, ostiolo suffuso tandem prominulo nonnihil ambitu dealbato, hymenio matrice imposito, paraphysibus adglutinatis rectis oleoso-grumosis. Sporæ in ascis elongato-clavatis oblongæ 3-septatæ incolores, longit. 0.028, crassit 0.008 mm. Ad arborum cortices. 34. Verrucaria (Thelidium) calcarea, n. sp. Thallus atro-fuscus tenuissimus irregulariter effusus v. nullus. Apothecia minuta (diam. 0.25 mm.) innato-sessilia hemisphærica v. convexa,

Lichenes.

ostiolo minuto simplici, excipulo proprio dimidiato atro, paraphysibus nullis(!). Sporæ in ascis clavatis ovatæ equaliter 2-cellulæ hyalinæ, longit. 0.018, crassit 0.009 mm. Ad calcem in regionibus calcareis. Obs.—V. olivacea, Fries. Sporæ diam. 3–4plo longiores. V. pyrenophora, Ach. Sporæ multum majores 3-septatæ. Description of Plates XXXV.-XXXVIII. Obs.—Spores and asci X 930, unless otherwise noted. Sections of apothecia and drawings of thallus X 40, unless otherwise noted. Plate XXXV. Fig. 1. Arthonia lecideoides; (a) section of apothecium, (b) spores in ascus. 2. Arthonia lirellœformis; (a) thallus showing apothecia, (b) sect. of apothecium, (c) spores in ascus. 3. Arthonia spadicea; (a) section of apothecium, (b) spores in ascus. 4. Arthonia suffusa; (a) spores in ascus, (b) section of apothecium, (c) showing the texture of lamina sporigera. 4a. Arthonia stictaria; spores in ascus. 4b. Arthonia pellucida; single spore. 5. Arthonia conspicua; spores in ascus. 6. Arthonia verruculosa; (a) thallus showing apothecia, (b) section of apothecium, (c) two spores. 7. Arthonia aspera; (a) section of apothecium, (b) two spores. Plate XXXVI. Fig. 8. Verrucaria macrocyrtospora; (a) spore, (b) ascus, (c) section of apothecium. 9. Verrucaria trachyspora; spores in ascus. 10. Verrucaria arthoniza; (a) spores in ascus, (b) section of apothecium x 80. 11. Verrucaria calcarea; spores in ascus. 12. Verrucaria suffusa; (a) section of apothecium, (b) spores in ascus. 13. Verrucaria submargacea; (a) spores in ascus, (b) single spore, frequent variety. 14. Verrucaria metabolica; (a) portion of thallus showing two apothecia, (b, c, d) three asci showing varieties of spores. 15. Verrucaria subatomaria; (a) section of apothecium, (b) spores in ascus. 16. Phlyctis stromaphora; (a) spore, (b) section of apothecium. Plate XXXVII. Fig. 16a. Thelotrema farinaceum; (a) spore, (b) section of apothecium. 17. Phlyctis cyrtospora; (a) section of apothecium, (b) spore, (c) spores in ascus. 18. Ascidium manosporum; (a) spore X 900, (b) spore X 540, (c, d) two spores discovered in same apothecium X 330, (e) section of apothecium. 19. Stigmatidium confluens; (a) thallus showing apothecia, (b) section of apothecium, (c) single spore. 19 a. Ascidium attenuatum; spore in ascus. 20. Ascidium fusiforme: (a) section of apothecium, (b) spore. 21. Lecidea cinnabaroides; spores in ascus. 22. " " section of apothecium.

Plate XXXVIII. Fig. 23. Fissurina monosporum; (a) spore, (b) section of apothecium. 24. Pertusaria fumosa; (a) section of apothecium, (b) spores in ascus. 25. Fissurina cyrtospora; (a) section of apothecium, (b) spores in ascus, (c) spore, (d) thallus showing apothecium. 26. Bacidia minutissima; (a) section of apothecium, (b) straight spores in ascus, (c) arcuate spores in ascus. 27. Pertusaria leucodes; (a) section of apothecium, (b and c) two spores X 900, (d) spores in ascus X 330. 28. Bœomyces novœ-zealandiœ; spores in ascus. 29. Lecidea clathrata; (a) section of apothecium, (b) spore. 30. Arthonia tenuissima; (a) section of apothecium, (b) spore.