254 DR. LINDSAY ON THE SPERMOGONES AND 
small black dots, perched on the tops of separate thalline warts. Spermatia are acicular, 
do X zs boo; the sterigmata either simple and digitately divided below, as in .4bro- 
thallus oxysporus, or consisting of a few irregularly jointed articulations. 
Specimen 6. Var. affinis, Sch. (Nyl. Prod. p. 145). On the trunks of firs, at the base 
of Mount Minenem: Scher. Exs. No. 629, sub Lecidea affinis. On the left-hand specimen 
in my copy (original ed. 1852) (the right-hand specimen being L. grossa, Pers.), spermo- 
gones are plentiful as small black dots, tipping separate thalline warts, exactly as in the 
type. Spermatia and sterigmata are also those of the type, the former acicular, z555 
long, the latter very delicate, and composed of few articulations. 
Species 20. L. vERMIFERA, Nyl. (— Scoliciosporum, Mudd, Brit. Lich. p. 185,— L. holo- 
melena auctt. pr. p.). 
Specimen 1. On quartzose rocks about Ripperschwyl, Switzerland: Hegetschweiler, 
Scheer. Exs. No. 536. Spermogones are very minute black dots, scattered among the 
apothecia. Spermatia are rod-shaped, 5566 to yooo long; the sterigmata very short, 
linear, simple. These characters agree with those given by Mudd of the spermogones of 
L. vermifera and their contents; but they do not differ much from those of the spermo- 
gones of L. (Biatorina) holomelena, Hepp, as given in Mudd’s ‘Brit. Lich.’ p.178. The 
two lichens here contrasted are readily separable, however, by their sporidia, which, in the 
one case—the true holomelena—are ellipsoid and 1-septate; in the other, as its name 
implies, vermiform, 3-septate. 
Specimen 2. On sandstone-grit, near Battersby, Cleveland: Leight. Exs. No. 186, 
sub L. expansa, Nyl. The spermogones ‘are small black papillæ, resembling the perithecia 
of a Verrucaria, seated on the thin, smoothish, blackish or dark-grey thallus, very abun- 
dant, much more so than the apothecia, which are sparsely scattered. Usually they are 
distinctly ostiolate. The spermatia are very short, suboblong, seated on the tips of very 
short, linear, simple sterigmata. Basal cellular tissue deep brown. 
Species 21. L. DECOLORANS, Hffm. 
Specimen 1. On ground, moors about the Storr, Skye, Aug. 1856: W. L. L. Sper- 
mogones are very abundant on specimens barren of apothecia, as small but distinct, 
round, olive or leek-green-coloured tubercles, seated on, sometimes tipping, white thal- 
line warts, frequently very superficial, aggregated occasionally in roe-like masses. They 
have the same colour frequently as the apothecia; but the contrast between their dark 
green and the whiteness of the thallus renders them always easily recognizable. Some- 
times only an ostiole is obscurely visible; it is more usually elongated than round. The 
spermatia are rod-shaped, very minute, subatomic in size, 55 X 50400 scarcely 
visible under power 380 of Nachet's microscope; borne on the apices and sides of arthro- 
sterigmata, which are very delicate, longish, ramose, irregular, so indistinct that they are 
with diffieulty visible, composed of short, subspherical cellules. 
Specimen 2. On peaty ground, Switzerland: Scher. Exs. no. 214, sub Lecidea granu- 
losa, Ach.: form with black apothecia. Spermogones are flattened cones, resembling very 
young apothecia, crowning whitish thalline warts. Spermatia are rod-shaped, about 
