^{page 513 note *} Vide Author's “Contributions to New Zealand Botany,” 1868, p. 22Google Scholar; “Otago Lichens and Fungi,” Transactions of Royal Society of Edinburgh, vol. xxiv. p. 407Google Scholar; “Parasitic (lichenicolous) Micro-Lichens,” Quart. Jour, of Micro. Science, January 1869Google Scholar; “Polymorphism in Fructification of Lichens,” Quart. Jour, of Micro. Science, January 1868.Google Scholar

^{page 513 note †} E.g. “Enumeration of Micro-Lichens parasitic on other Lichens,” Quart. Jour, of Micro. Science, January 1869.Google Scholar

^{page 514 note *} Vide Author's “Otago Lichens and Fungi,” p. 434Google Scholar, and Arthonia melaspermella, Journal of Linnean Society (Botany), vol. ix. p. 269.Google Scholar

^{page 515 note *} In various letters Mr Berkeley has expressed himself as follows:—“So convinced am I of the near relation of lichens and fungi that in the portion of my ‘Introduction to Cryptogamic Botany,‘ which is printed, I make one division, Mycetales, to include Fungales and Lickenales” (July 1856)…. “One or two Verrucariæ are so near Sphæriæ that it is almost impossible to draw the line” (Dec. 1856)…. “It is quite impossible to distinguish some lichens from fungi, and I consider the whole series as a division of fungals” (Feb. 1869). I hold quite as decided an opinion as to the impossibility of distinguishing many lichens from many fungi; or, in other words, of referring members of the group of fungo-lichens to the group of fungi rather than to the lichens! But I regard any classification, which arranges lichens as a co-division with fungi of a group of fungals, as imperfect, artificial, and arbitrary, excluding as it does the equally close alliance that subsists between lichens and Algæ.

^{page 515 note †} His views and my objections are fully given in a subsequent part of the present memoir (pp. 528–580).

^{page 515 note ‡} “Otago Lich. and Fungi,” p. 436; Arthonia melaspermella, p. 279.

^{page 515 note §} As determined by Mr Currey, who wrote me in February 1866 as to “a curious species of Torula” (contained in my Herbarium) “which I do not recognise as having seen before. It is ramose, with bluish or greenish-black joints, the cells of which measure from 0·0003 to 0·0005 inch.”

^{page 515 note ∥} E.g. those described in Körber's “Parerga,” p. 452, et seq.

^{page 516 note *} E.g. Dichæna rugosa, Fr.

^{page 516 note †} Vide author's “Memoir on Spermogones and Pycnides,” Trans. Royal Society of Edinburgh, vol. xxii. plates iv. v. vi. vii. viii. xi. xii.Google Scholar

^{page 518 note *} Vide p. 520, and foot note †.

^{page 519 note *} (b) P. 540.

^{page 519 note †} I have seen true Lichen-sporidia by cohesion acquiring characters closely resembling those concatenate and woolpack-like forms of the spores of Coniothecium lichenicolum (pi. xxiii. fig. 28), e.g., in Lecidea dubia, T. and B., Leight. Exs. No. 88. In several other cases, I have met with Lichensporidia cohering in such manner as to resemble cellular tissue, e.g., in Verruearia subalbicans, Leight. Exs. No. 200.

^{page 519 note ‡} Vide p. 515, and foot note ‡.

^{page 519 note §} “Otago Lich. and Fungi,” p. 436.

^{page 520 note *} Vide p. 516, and foot note †.

^{page 521 note *} So long ago as July 1856, Mr Berkeley wrote me—“You are aware, probably, that in a species of Tympanis, Mr Broome and myself have seen on the same hymenium the spores of a Diplodia and true asci. Tulasne doubts Mr Broome and myself having seen stylospores on the paraphyses of a lichen. Nothing, however, was more clear and free from illusion. Almost in the same breath Tulasne calls in question the correctness of Hooker and Babington's observation. He should not do this. I sent Tulasne the very section we had seen the stylospores of the lichen in, but he could see nothing. Unfortunately, there were but two or three scattered apothecia on the roots of Ammophila, sent for a fungus by Gardiner. I have in vain tried to get more from the same locality.” (Vide also my “Monogr. Abrothallus,” p. 55; Nylander's “Prodromus,” p. 55; Berkeley's “Brit. Fungology,” p. 87, plate i. fig. 13.)

In December of the same year Mr Berkeley again wrote me (in regard probably to Abro thallus Smithii)—“In American specimens of your plant I sometimes find asci, sometimes naked spores, which have the same relation to the asci that the stylospores of Diplodia to the asci of the Sphæria to which they belong. Whether the production in question is a lichen or fungus is a knotty point. It grows on living bark, and therefore should be a lichen!”

^{page 522 note *} Arthonia melaspermella, p. 283; “Otago Lich. and Fungi,” p. 423; “Parasitic Micro-lichens.”

^{page 523 note *} “Handbook of Organic Chemistry,” 4th edition (1856).Google Scholar

^{page 523 note †} “Dictionary of Chemistry,” 5 vols. (1860–68)Google Scholar.

^{page 523 note ‡} Quoted in “Chambers's Encyclopædia,” 10 vols. (1860–68)Google Scholar.

^{page 523 note §} “Elements of Chemistry,” 2d. ed. (1849).Google Scholar

^{page 523 note ∥} Miller, (“Elements of Chemistry,” 2d ed., 1862, p. 597”Google Scholar) gives Datiscine ( = C₄₂H₂₂O₂₄), as the colorific principle of Datisea cannabina—not as a starch!

^{page 524 note *} “On Chemical Reaction as a Specific Character in Lichens,” Journ. of Linn. Soc. vol. xi. (Botany), p. 36Google Scholar; and “Experiments on Colour-reaction as a Specific Cnaracter in Lichens,” Trans. Botanical Society of Edinburgh, vol. x.Google Scholar

^{page 525 note *} The term, “gelatine” or “mucilage,” is here used, and by lichenologists generally, in a popular, not in a strictly chemical, sense; for it has already been shown that the so-called “gelatine” may really be a form of starch or gum, or a mixture of forms of either or both! Compare Arthonia melaspermella, p. 283.

^{page 525 note †} It is faint or obscure in the following, and in many other, true lichens:—

Collema turgidum, Schær. Exs. 433. Asci.

Stereocaulon condensatum, Schær. Exs. 509. Asci.

Calicium stigonellum, Leight. Exs. 22G. Asci.

Lecidea Wahlenbergiana v. truncigena, Ach., Leight. Exs. 123. Hymenium, mere trace.

^{page 525 note ‡} In his “Prodromus” he describes some species as possessing a yellow reaction, e.g. V. xylina (p. 191).

^{page 526 note *} The majority of lichenological systematists give no attention to chemico-botanical characters, e.g., Massalongo, Körber, Th. M. Fries and Mudd; while Nylander, on the contrary, gives them decided prominence, e.g., in his “Lich. Scand.”

^{page 527 note *} In Berkeley's, “British Fungology” (1860) p. 375Google Scholar, both Agyrium and Xylographa figure among fungi, the latter having rank as a subgenus under Stictis. A. rufum and X. parallela are mentioned; but not X. flexella (unless it be as Peziza flexella, Fr., p. 371), which, however, appears associated with X. parallela in Nylander's “Prodromus,” p. 148, as a lichen.

^{page 527 note †} “Parasitic Micro-lichens;” Arthonia melaspermella, p. 284.Google Scholar

^{page 528 note *} Quoad the asci and sporidia it also resembles Lecanora cervina, Pers., Lecidea morio, Sch., L. fossarum, Duf. of Nylander's Exs., and L. pruinosa, Sm.

^{page 528 note †} “I think,” writes Mr Berkeley, in Feb. 1869, “Tulasne is quite right in making Phacopsis, Abrothallus, Celidium, and Scutula lichens.”

^{page 528 note ‡} Vide my “Monograph of Abrothallus,” Quart. Journ. of Micro. Science, Jany. 1857.Google Scholar Nylander (Prod. 55) remarks, “Nullam enim mihi obtulit notam lichenosam.” But what constitutes a “Nota lichenosa?” What diagnostic is there characteristic of a lichen as contradistinguished from a fungus? For my own part, I know of none!

^{page 528 note §} I have never myself met with in lichens a yellow iodine-reaction, which I did or could not regard as the natural (unchanged) colour of the reagent itself.

^{page 529 note *} Arthonia melaspermella, p. 282.

^{page 530 note *} “Otago Lich. and Fungi,” pp. 436–442.

^{page 530 note †} An excellent illustration is to be found in the group of “Parasitic Micro-lichens,” (anteaa citat.)

^{page 532 note *} Vide “Mem. Spermog.” Plates IV. V. VI. VIII. XL XII.

^{page 532 note †} Vide Paper on “Parasitic Micro-Lichens.”

^{page 533 note *} Vide p. 532 and foot note.

^{page 534 note *} Transactions of Linnean Society of London vol. xxv.

^{page 535 note *} I have recently (August 1869) found Coniothecium frequent on the sterile saxicolous thalli of Lecanoræ, both in the northern and southern Highlands, e.g., Helmsdale, Sutherlandshire, and St Mary's Loch district, Selkirkshire. In these districts the thalli in question are most probably referable to Lecanora parella or glaucoma, or both. On similar sterile thalli the parasite is common throughout Scotland, and probably throughout Britain.

^{page 536 note *} Vide p. 519 and foot note.

^{page 536 note †} P. 45, tab. 1984, 2d ed., 1843.

^{page 536 note ‡} The specimen of S. Graphideorum, Nyl., contained in my copy of his “Herb. Lich. Paris,” No. 72 (from Fontainebleau, on a white, mealy thallus—of some Graphis—coating a very rugged bark, and associated with a Hysterium), has the external characters, on a large scale, of a Spiloma. Spiloma nigrum, var. variolosum, Turn. & Borr. in Leighton's Exsic. No. 259, closely resembles it, though Leighton's plant is more crowded and more irregular in outline. The French Spilomium is quite visible to the naked eye; variable in size; very black; irregular in outline, though generally round; sometimes confluent; surface usually more or less convex and rough, as in Coniothecium, from the projecting powdery or granular spore-masses. The spores are spherical or oval; generally with double contour; simple; deep brown; about ·00025“ in diameter; sometimes slightly irregular in outline; cohering frequently in rouleaux like blood-corpuscles.

^{page 536 note §} = Spiloma sphœrale, Ach., but not Buellia saxatilis, Schær. (Nylander, “Prod.” p. 140), according to Th. Fries (“L. Arct.” p. 116).

^{page 537 note *} Transactions of the Royal Society of Edinburgh, vol. xxiv.

^{page 537 note †} Transactions of the Linnean Society, vol. xxvii. (1869).Google Scholar

^{page 538 note *} “Lichenes Spitsbergenses,” p. 36. Vide also author's “Observations on Greenland Lichens.”

^{page 539 note *} What was originally designated Alectoria, is now known as Neuropogon, Taylori (Nyl. “Syn.” p. 273).

^{page 539 note †} “Otago Lichens and Fungi,” p. 441, pi xxx. figs. 31–34.

^{page 540 note *} Frequently erroneously written solæform. Soleaform sporidia are necessarily 1-septate. Vide definition of the term in “Otago Lich. and Fungi,” foot note, p. 447.

^{page 540 note †} Vide p. 519.

^{page 541 note *} Frequently erroneously written solæform. Soleaform, sporidia are necessarily 1-septate. Vide definition of the term in “Otago Lich. and Fungi,” foot note, p. 447.

^{page 542 note *} Vide Paper on “Parasitic Micro-Lichens” (antea citat.).

^{page 542 note †} And in New Zealand: Lindsay, “Obs. on N. Z. Lichens,” p. 540.

^{page 543 note *} A genus not mentioned in Berkeley's, “British Fungology” (1860).Google Scholar

^{page 543 note †} Vide Paper on “Parasitic Micro-Lichens” (antea citat.).

^{page 545 note *} It may also be compared with his Lecidea oxysporella (Prod. 145), which grows on the thallus of C. digitata on the Splügen; and with Lecidea Cetraricola, Linds. (“Lichenicolous Micro-Lichens,” Quart. Journal of Microscopical Science, Jan. 1869).

^{page 545 note †} I have pointed out the anatomical or morphological distinction between stylospores and spermatia in my paper on “Polymorphism in the Fructification of Lichens” (antea citat.).

^{page 546 note *} In my MS. Notes on Moore's Irish Lichens—made in 1858—I named this parasite provisionally Abruth. Cladoniarum, but any such specific designation is apt to lead to confusion with Nylander's Lecidea Cladoniaria.

^{page 546 note †} Vide Paper on “Parasitic Micro-Lichens” (antea citet.).

^{page 548 note *} Two specimens of S. Hookeri (sub-nom. Verrucaria), which I examined in the Kew Herbarium, had the following characters:—

1. Summit of Ben Lawers. Thallus Parmelioid, pale yellowish-white. Perithecia are quit those of a Verrucaria; seldom, however, forming regular cones or papillæ; more usually flattened and irregular as to form and size. None of the hymenial elements give blue with iodine. Sporidia broadly ellipsoid, tapering suddenly at the tips; 3-septate; becoming by longitudinal sub-division of the loculi sub-muriform; deep brown; ·001“ long, ·0005“ broad.

2. Gemmi, Switzerland. Perithecia much larger and ostioles more distinct; immersed or semiimmersed; bursting through the cortical layer of thallus, with—at least usually at first, in their young state—stellate fissuring. Thallus here again Parmelioid and simple; usually buff-coloured, sometimes pale green. The plant has an Endocarpoid facies.

In both cases the perithecia occur by themselves on a thallus, which appears to belong to them. It seems to me that it is the same plant that occurs sometimes with a proper thallus (Verrucaria), and at other times as an athalline parasite (Sphæria); that it has equal claims to rank as a Sphæria or Verrucaria; and that it matters little whether it is classed among the Sphæriæ or Verrucariæ—fungi or lichens—provided only fungologists and lichenologists would come to some common understanding regarding it!

^{page 550 note *} Quarterly Journal of Microscopical Science, vol. v. 1857Google Scholar.