116 



LICHENACEI. 



[STEREOCAULO*. 



Tribe V. STEREOCAULEI Nyl. Mem. Soc. Chorb. iii. 



(1855) p. 170. 



Thallus casspitose, erect or decumbent, with solid fruticulose 

 podetia, to which are affixed fragile, more or less evanescent gra- 

 nules, usually bearing cephalodia, internally with chondroid axis. 

 Apothecia lecideine, rarely lecanorine, terminal and lateral, para- 

 physes discrete ; spores 8nse, sometimes 6na3, variously septate, very 

 rarely solitary and murali-divided, subfusiform, cylindrical or oblong, 

 colourless. Spermogones immersed, with simple sterigmata. 



Though resembling the Sph&rophorei in the fruticulose habit, this 

 tribe is far separated by the grauulose thallus and by the structure of the 

 apothecia. From the preceding, to which it is closely allied, it differs in 

 the absence of the thick subhymenial stratum. As observed by Nylauder 

 (Lapp. Or. p. 177), it precedes, like the Pilophorei, the Cladoniei, since 

 the granulose thallus expresses a lower type in the series. 



29. STEREOCAULON Schreb. Gen. PI. (1791) p. 768: Nyl.Syn. 

 i. (1860) p. 230. Podetia branched, somewhat rounded, covered o r 

 sprinkled with gra- 

 nules of various forms, 

 internally with a car- 

 tilaginous axis formed 

 of longitudinal conglu- 

 tinate chondrohyphas, 

 to which are affixed 

 the external portions 

 of the thallus, viz. a 

 corticali-gonidial and 

 an arachnoid medul- 

 lary layer. Apothe- 

 cia biatorine, blackish- 

 brown or pale brown- 

 ish, rarely lecanorine, 

 black ; hypothecium 





r ) 



d 



colourless ; spores 8na3 



Fig. 33. 



or 6nae (in subclavate SforeocaBfon coralloides Fr.-a. Vertical section of 

 thecas), fusiformi-cylin- a n apothecium, x30. b. Theca and paraphysi*. 

 drical, 3- or pluri-sep- X350. c. Spores, X500. d. Vertical section 

 tate: paraphvses dis- of a young spermogone, x30. e. Sterigmata, 

 tinct, slender or mode- and/ ' -P"*^ X50- 

 rate ; hymenial gelatine bluish with iodine. Spermogones lateral 

 or subterminal in pale conceptacles, blackish at the apices, with 

 spermatia aciculari-bacillar, straight, or longer and slightly curved. 



Many plants belonging to this genus have an elegant appearance with 

 then* fruticulose granulate podetia and numerous brown or dark apothecia. 

 The podetia, especially in barren specimens, are sometimes whitish 

 sorediato-capitate. The apothecia, which arise from the granules, are at 

 first punctiformi-impressed, and then lecanoroid, becoming immediately 

 lecideine (biatorine). Our British species, which belong to tho subgemis 

 EtutereocauloK) have the thalline reactions K+yellow, CaCl~, except in 

 S. coralloides, where the chondroid axis is K+yellow. 



