﻿The genus Teloschistes in North America 



R. Heber Howe, Jr. 



The genus Teloschistes* which was proposed by Norman 

 (Conat. gen. nuUull. Lich., Nyt. Mag. Naturvid. 7: 228. pi. i, 

 f. 4 a-g. 1853) included under his division "(a) Thallus 

 fruticulosus," beside the type species, T. flavicans (Sw.) Norm., 

 only one other, T. villosus (Ach.) Norm., though under two other 

 sections, i. e., Phyllothallae and Placothallae, he placed nine addi- 

 tional species, which have since found their proper positions in sev- 

 eral other distinct genera. As both of the above named species are 

 characterized by a radial thallus it is not surprising to find that 

 later in 1861 (Gen. Het. Recog. 51) Th. Fries logically limited 

 the genus to include only these two species and the radial Lichen 

 chrysophthalmus L. The authors who have included bifacial 

 (dorsiventral) species in Norman's genus have no good arguments 

 in their favor, as recently pointed out by Monsieur Hue. 



The present species have been found from time to time in many 

 genera as follows: Lichen L., 1771; Usnea Hoffm., 1795; Parmelia 

 Ach., i^OT,\ Physcia Michx., 1803; Borrera Ach., 1810; Cornicularia 

 Pers., 1826; Evernia Fries, 1831; Hagenia Rbhn., 1850; Blastenio- 

 spora Trevis., 1853; Tornabenia Massal., 1853. 



TELOSCHISTES Norm. em. Th. Fries 

 Description: Thallus caespitose or prostrate, branched, with- 



out rhizoids; cortex glabrous or rugose-lacunose ; 

 (hyphae parallel in the surface); laciniae terete, subterete or 

 angularly compressed; cinereus or yellow; medulla and axis 

 arachnoid, simple. Gonidia stratified (heteromerous) : Proto- 

 coccoid. Soralia normal. Cephalodia unobserved. Apothecia le- 

 canorine, terminal or marginal; scutelliform, applanate or con- 

 cave, rarely convex; marginate, disk concolorous. Asci clavate, 



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