LEPTOGIUM. 163 



dling-sized, laciniate, more or less strongly and reticulately 

 wrinkled; lead-coloured; made up of longish, much-divided, 

 now wider and depressed and now narrowed and (from below) 

 branch-like segments, with plicate undulate and crisped, rather 

 entire edges ; apothecia minute, marginal, biatorine, from globu- 

 lar becoming flat ; the disk rufous, the rather stout, paler mar- 

 gin granulate, and encircled at length with a ring of leaflets. 

 Spores ovoid-ellipsoid, sub-muriform (the transverse series of 



spore-cells 4-6), decolorate, ^ mic. Mont. Cuba, p. 115. 



Tuckerm. Gen. p. 98. Collema vesicatum, Tayl. 1. c. 1837, p. 196. 

 Leptogium corrugatulum, Nyl. Syn. I, p. 132. 



On bark. Southern Alabama (J. F. Beaumont), Tuckerman 

 I. c. 1872. Florida, Eavenel. Texas, Hall. Mexico, Galeotti, e 



Nyl., as in the West Indies. Sufficiently distinguished always 



from L. Tremelloides by its longer, more divided, and wrinkled 

 divisions ; and the plant occurring now (exactly as the next spe- 

 cies) in a wider, depressed state, and now in a narrowed and 

 crisped one. Leptogium corrugatulum, Nyl. I. c. (Herb. Lindig 

 n. 2659) is quite the same with the earlier Collema vesicatum, 

 Tayl. I. c. (herb.), and relates to the depressed and more promi- 

 nently wrinkled condition of the lichen described by Swartz, 

 Acharius, etc. The fruit is the most important feature of the 

 plant ; and this is exactly the same in both forms. 



18. L. chloromelum (Sw.) Nyl.; thallus middling to ample, 

 orbiculate, becoming rigid, sharply wrinkled, and at length 

 densely granulate ; dark-green, and lead-coloured ; the lobes of 

 the circumference expanded more or less, those of the centre 

 -complicate, and crisped; apothecia middling-sized, lecanorine, 

 sub-sessile ; the flattish, rufous disk bordered by a thin, plicate- 

 rugose, now granulate, thalline margin. Spores ovoid- and 

 acuate-ellipsoid, sub-muriform (transverse series of spore-cells 



4-6), soon decolorate, ^ mic. Nyl. Syn. \,p. 128. Tuckerm. 



Gen. p. 98. L. Brebissonii, Mont., pro p. 



a. conchatum-, thallus sub-monophyllous, becoming lobate- 

 laciniate; the depressed, rounded lobes ascendant, shell-like, 

 gyrose-plicate. 



b. stellans', thallus narrowed; the radiant divisions with 

 erect, crisped edges. 



Trunks and rocks throughout the United States, Tuckerman 

 Gen. 1872. Canada, Drummond. New England, Dr. J. Porter, 





