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Verrucaria, Bagliettoa, Acrocordi sp., Thelidium, Polyblastia max. p-; 
& Sporodictyon, Koerb. Parerg. in locis. Verrucaria, Acrocordiz sp., 
Sagedia pro p., & Thelotrematis spp., Anz. Catal. Sondr. in locc. 
Thrombium, Verrucaria, Acrocordie sp., Thelidium, Polyblastia & 
Sporodictyon, Th. Fr. Gen. in loce. Verrucaria, Thelidium pro p., & 
Spheromphale pro p., Mudd Man. Brit. Lich. in loec. Thrombium, 
Verrucaria, Limboria, Arthopyrenia pro p., Polyblastia, & Sporodictyon, 
Stizenb. Beitr. 1. c. in locis. 
Structuram descripserunt Tulasne Mém. sur les Lich. pp. 51, 57, 90, 
t. 13, f. 1-18; Fuisting 1. c. p. 45. 
Apothecia innato-prominula, perithecio atro, amphithecio pallido 
1, dein nigricante, paraphysibus tenuibus plerumque indistinctis ]. 
diffluxis. Spore ovoideo-ellipsoidex, e simplici bi-quadriloculares, 1. 
demum mnuriformi-multiloculares, subincolores. Spermatia (quantum 
obs.) acicularia; sterigmatibus simplicibus. Thallus crustaceus, sub- 
tartareus, uniformis, rarius areolato-squamulosus. 
The rock- and earth-Verrucarie are not only of distinctly higher rank 
than the corticoline groups here brought together under Pyrenula ; but 
we find also, if I mistake not, an appreciable, general difference, of which 
there is no trace in the analogous portions of Biutoreei and Eulecideei, in 
the spores. We cannot distinguish in this way the saxicoline types of the 
higher groups just referred to, from the corticoline. But oneshall hardly 
compare the spores of Verrucaria, as the genus is understood in this 
place, exhibiting, with regularity of expression, the successive steps in 
the differentiation of its spore-type, from the simple (Verrucaria, Koerb. 
Syst.) to the bi-quadrilocular (Thelidium, Mass.) and finally the muriform- 
multilocular condition (Polyblastia max. p., Mass.) with the heap of varied. 
and irregular forms which characterize Pyrenula (Fée, Naeg. & Hepp, 
emend.) without acknowledging that we have, in the groups first and last 
named, two distinct exhibitions of the (normally) coloured spore. 
As here taken, Verrucaria is then a group of genuine lichens, with 
distinct and often conspicuous thallus, and a full and harmonious spore- 
character, which is regarded as separable from closely related groups, on 
the one hand by its carbonaceous exciple, and on the other by subtle but 
appreciable conditions, dependent, it is presumed, on these plants being 
confined to inorganic substrates. 
Only some fifteen or sixteen specific forms of Verrucaria, as under- 
stood here, were recognized by Fries. The number hassince been greatly 
increased; and as now reckoned, in the latest German revisions, exceeds 
ninety. These have in part been determined since the date of Nylander’s 
monographical exposition of the tribe: in the latter however it is observ- 
able that only twenty-seven species are admitted. About two-thirds of 
