N. 



Fig. 47. 



Ricasolia amplissima Leigbt. a. Vertical section of a young apothecium, X30. 

 b. A theca and paraphysis, X 350. c. Spores, x 500. d. Vertical section ot" 

 a spermogone, X 30. e. Jointed sterigmata and sperniatia, X 500. 



species occur in the more humid tracts of our islands. The tribe has 

 been divided by Nylander into the following 2 subtribes, comprising 

 5 genera, founded npon differences in the structure and character of the 

 thallus, the presence or absence of cyphellse, arid the nature of the apo- 

 thecia. 



Subtribe I. STICTINEI Nyl. Flora, 1879, p. 360. 



Thallus either cyphellate or ecyphellate beneath ; gonidial layer 

 consisting of gonimia arranged in pluri-locular nodules. Apothecia 

 lecanoroid, rarely parmeleine. 



Distinguished by the nature of the gonidial layer, which separates it 

 as a very distinct subtribe. The plants are easily recognized by this 

 layer presenting under the lens, or even to the naked eye, a bluish or 

 leaden-bluish appearance. 



44. STICTINA Nyl. Flora, 1860, p. 66, Syn. i. p. 333. Thallus 

 variously lobate or laciniate, often sorediiferous ; beneath cyphellate 

 or pseudocyphellate, with simple rhizinae (rhizo7iypJice~Nyl.') ; gonimia 

 often 2-3 moniliform. Apothecia usually with septate spores. 

 Spermogones innate, not prominent, with spermatia somewhat short, 

 obtusely and slightly thickened at either apex. 



