CON Tl: NTS 



Page. 



Letter of tkansmittal xi" 



iNTKODUCilON 1 



Plant localities K' 



Location ami gcolo{;y of tbo Potomac beds •'■! 



Location of tin) Potomac lieils -i-t 



Geology of the Potomac boils 1" 



Geological position and origin of the lower Potomac beds .'>8 



Desckiption ok the si'kcies 63 



Cryptogams tJ-5 



Einiisetcaj <>3 



Kilices '>'> 



Phanerogams !(>*> 



Gymnosperniiu 166 



Zamieic lt><' 



Couifene lS':t 



Gymnoapermoiis fruits -6"2 



Undetermined plants '■J''! 



Angiospermio -77 



General remarks and ronclusions •VJti 



List of Potimiac plants :«(! 



Geological allisiities of the Potomac plants 3:i:i 



Eqniseta :!:!! 



Ferns 3:55 



Cy cads 'Ml 



Conifers 343 



Angiosperms 346 



Tables 349 



Index 373 



[The i>lates are bound in a separate volume.] 



