LICHENES. 123 



but becoming flat, and at length, especially on the branches, larger, 

 crenate, and more densely heaped, glaucescent. Cephalodia sessile, 

 scrobiculate-foveolate, of about the color of the phyllocladia. Apo- 

 thecia subterminal, of middling size, flat, but at length nearly exclud- 

 ing the thick white margin, when the disk becomes turgid, and the 

 remnant of the now colored thalline border appears as a thin, pale, 

 proper margin. Spores of the genus. I should refer this Lichen to & 

 leporinum, Th. Fries (De Stereoc. Comm. p. 25), but the author of the 

 species named, now refers it to S. sphcerophoroides, Tuckerm. (Enum. 

 N. A. Lich. p. 52), which is quite different from the present. 



3. Stereoc aulon paschale, (Linn.) Fr. 



Lichen paschalis, Linn. Sp. PI. p. 1631, & Fl. Suec. n. 1120, e. Fr. infra cit. 

 Stereocaidon paschale, Ach. Meth. p. 815, etc. pro parte ; Fr. Lichenogr. p. 202 ; 

 Tuckerm. Syn p. 45, & Lich. Exs. n. 112. 



Hab. Fuegia, a dwarf form, with flattened podetia. 



4. Stereoc aulon denudatum, Floerk. 



Stereocaidon denudatum, Floerk. D. Lich. 4, p. 13, n. 79, fide Somnierf. Suppl. p. 

 126; Laurerin Fr. Lichenogr. p. 204; Moug. & Nestl. Crypt, n. 446; Tuckerm. 

 Lich. Exs. n. 114. 



Hab. Summit of Pico Ruivo, Madeira. St. Jago, Cape Verde 

 Islands. — Exactly agreeing with specimens collected near Naples, of 

 S. Vesuvianum, Pers. ; which is referred, I think correctly, to the pre- 

 sent species, by Dr. Nylander (Enum. Gen. 1. c. p. 97). 



5. Stereocaulon tenellum, Sp. Nov. (Tab. 2, fig. 2.) 



S. thallo ccespitoso purnilo gracillimo a basi vage apicemque versus fas- 

 tigiato-ramoso tenuiter tomentoso glauco-albescente ; phyllocladiis spar- 

 sis miniisculis rotundatis mox pulveraceis ; apotheciis ignotis. 



Hab. Near Lima, Peru. 



