81 



179. Thallus leaf-like r or scale-like. ENDOCARPEI. 

 Thallus crustrlike. VERRUCARIEI. 



180. Thallus crust-like, adhering to its support. LECIDIBI. 

 Thallus horizontal, thread-like. C.ENOGONIEI. 

 Thallus consisting of two parts. The horizontal part scaly or crus- 

 taceous, sometimes disappearing soon ; vertical part with an appar- 

 ent stem. CLADONIEI. 



181. Thallus mostly thread-like, and of nearly uniform character in 



all parts, erect, or at length hanging down. USNEEI. 

 Thallus crust-like when dry. 181, b. 

 Thallus leaf-like when young, and not gelatinous. 



Thallus rising obliquely, variegated underneath by veins or marks. 



Gonidia green or bluish. PELTIQEREI. 

 Thallus horizontal. 



Thallus furnished with fibrils on the under surface. PARMELIEI. 

 Thallus joined centrally to its support by a stem-like cord. 



UMBILICARIEI. 



Thallus at length becoming scale-like, and in some places dimin- 

 ished to a crust, resting on a plain hypothallus. PANNARIEI. 



181, b. Thallus gelatinous when wet, rarely thread-like, sometimes 

 leaf-like when young, but diminishing at length to a crust. Goni- 

 dia of a peculiar character. COLLEMEI. 

 Thallus not gelatinous, sometimes uniform, sometimes figured. 



LECONOREI. 



FUNGI. 



Ascus, a minute sac usually long and club-shaped, in which sev- 

 eral spores are formed. 



Basidia, elongated or club-shaped cells, bearing one, two, or four 

 spores at their points. 



Gonidia, cells or spores not resulting fronc fertilization, often 

 formed in bead-like strings, and thrown off one by one, capable 

 of sprouting to form new plants. 



