LL. Lesquereux on the Coal Formations of the United States. 17 
prom 
serious botanical studies. 
comparative anatomy has done more for animals than for plants. 
ut t 
- Certainly ref their proper genus. For what concerns 
families of ne cal aie B68 ei I think that the recon- 
structions offered by comparative anatomy are as reliable for 
Lepidodendron, Sigillaria, for whole forests indeed rebuilt from 
Am. Jour. Sct.—Srconp Sertes, Vor. XXXII, No. 94,—JuLy, 1861, 
3 
