132 LICHENES. 



6. Endocarpon. Thallus crustaceous or cartilaginous often 

 lobed or foliaceous. Apothecia globose, imbedded in the thallus, 

 with a slightly prominent apex and including a nucleus. 



7. Pertusaria. 77i#//z/scartilagineo-membranaceous, spread- 

 ing, adnate, uniform. Apothecia verruciform, formed of the 

 thallus, one-or many-celled, each cell containing a nucleus, the 

 apex depressed, coloured, often distorted. 



8. Thelotrema. Thallus crustaceo-cartilaginous, spreading, 

 adnate, uniform. Apothecium double, the outer consisting of an 

 open ivart formed of the thallus, the inner (one or two) thin, 

 membranaceous, breaking away at the top, its disk containing a 

 nucleus. 



(True Lichens). 



c. Apothecia ? naked sporules (jgongyli or pulvinuli). 



FAM. V. LEPRARIEyE. 



9. Lepraria. Thallus crustaceo-leprose, spreading, adnate, 

 uniform. Apothecia none. Sporules naked, forming the thal- 

 lus, scattered and conglomerated, free. 



10. Spiloma. Thallus crustaceous, spreading, adnate, uniform. 

 Apotliecia none. Sporules naked, coloured, collected into com- 

 pact tumid masses. 



d. Apothecia opening into depressed or hollow shields or pustules 



(variola?). 



FAM. VI. VARIOLARIEiE. 



11. Variolaria. Thallus crustaceous, membranaceous, ad- 

 nate, spreading, uniform. Apothecium a suborbicular, scutelli- 

 form cup, formed of the thallus, filled with a powdery or floccu- 

 lose substance, which covers an immersed waxy disk containing 

 imbedded tltcca. 



e. Apothecia bordered, discoid, sessile (patelhda?). 



Fam. VII. Lecanore^:. 



12. Urceolaria. Thallus crustaceous, spreading, adnate, 

 uniform. Apothecia (patellulce) orbicular, the disk concave, colour- 

 ed, immersed in the crust, border formed of the crust and 

 of the same colour. 



13. Lecidea. Thallus crustaceous, spreading, adnate, uniform, 

 Apothecia (patelhdce) orbicular, sessile, plano-convex, having 

 a border of the same colour as the disk. 



14. Lecanora. Thallus crustaceous, spreading, plane, adnate, 

 uniform. Apothecia (pateUidce) orbicular, thick, sessile and 

 adnate, the disk plano-convex, its border thickish, formed of 

 the crust and of the same colour. 



