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as,in one way or other, referable to, or at least as exceptional forms 
associable with, the coloured series. Graphis itself affords much such a 
diversified exhibition of modifications of spore-structure referable, it 
should seem, to the normally brown type, as the variously analogous 
Thelotrema, and Pyrenula; and like these genera, it offers not seldom 
apparent, though perhaps not in fact irreducible anomalies, as well in the 
spores, as in the apothecia. 
The tribe is, as yet, far from fully represented here, even as respects 
northern forms. No Enterographa, nor Lithographa is known; and 
Platygrapha periclea has been observed but by a single lichenist. The 
larger part of the forms of ZLecanactis, all but one of the exclusively 
saxicoline Opegraphe, and even Graphis Lyellii, are strangers to us. It 
is possible that some of these are really wanting, but the most, as 
especially Lithographa (inhabiting granitic rocks in Sweden) and the 
calcareous Opegraphe may well be looked for.. The number of tropical 
Graphidacei reckoned as known to occur within our limits, is also smaller 
than should be expected, but will doubtless be enlarged when the lichens 
of the extreme south are more fully explored. Few herbariums are 
sufficiently rich in material for the profitable determination of these 
tropical species; and it is only quite recently that the Cuban collections 
of Mr. Wright, and the admirable ones of Lindig have put me in a 
position for attempting it. Most fortunately however, I have been able 
to avail myself, in almost all the more obscure southern forms, and in 
many of the northern, of the great knowledge of Dr. Nylander; whose 
illustrations of Graphidaceous types surpass in extent and importance 
those of any other lichenographer. 
Fam. 1.—LECANACTIDEI, Stizenb., salt. pr. p. 
Apothecia subrotundo-difformia, rarius elongata; marginata. 
XLVI.—LECANACTIS (Eschw.) Koerb., emend. 
Lecanactis, Koerb. Syst. p. 275 (additis Opegr. plocina, & Pragmopora 
premnea). Th. Fr. Gen. p. 93. Tuck. Obs. Lich. 1. c. 6, p. 283. 
Opegraphe sp., & Lecidee spp., Ach. L. U. pp. 32, 43. Scher. 
Spicil. p. 51, 204. Borr. in Hook. Br. Fl. 2, p. 144, 176, 179. Nyl. 
Prodr. p. 137, 151; Lich. Scand. p. 240; in Prodr. Fl. N. Gran. p. 70. 
Lecanactis pro p., Eschw. Syst, p. 14. Lecanactis, Pyrenothee sp., & 
Parmelie sp., pro p., Fr. L. E. p. 374, 450, 183. Lecanactis, Schis- 
mInatommatis spp., & Coniangii sp., Massal. Ric. p. 53, 55; Alc. Gen. 
p. 13. Schismatomma, Mudd Man. Brit. Lich. p. 222, non Flot. & 
Koerb. Lecanactis sect. 3, Stizenb. Beitr. 1. c. p. 156. 
Apothecia rotundata rarius oblonga, excipulo proprio integre 
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