346 Systematic Paleontology 



peduncle of Podozamites distantinervis Fontaine, with "which they are 

 most closely comparable. 



There is some variability with respect to closeness or remoteness of 

 the veins and in the character of the base in the various specimens which 

 the writer refers to this species but these variations are no greater than 

 are shown among the specimens which the original describer referred 

 to the type. For example, some of the specimens show a base which is 

 slightly subcordate, while in the specimen which Ward made the type of 

 Zamia ivashingtoniana, it is rather gradually narrowed, but no more so 

 than in some of the Glen Eose specimens which Fontaine referred to 

 Zamites tenuinervis. Again the typical forms of the latter have rather 

 close-set fine veins, while the poorly preserved specimens with more 

 remote veins but found associated with the others, were made the type 

 of Zamites distantinervis Fontaine, although the veins are no more re- 

 mote than in the G-len Eose specimens which the same author refers to 

 Zamites tenuinervis. In reviewing all of the material it is seen that 

 these minor variations and the variations in calibre of the veins due to 

 the state of preservation are not of specific value, and it is found im- 

 possible to frame any definitions which will permit the segregation of 

 these various forms. 



The cone which Ward figures from the Patapsco formation as the cone 

 of this species, while superficially suggesting a small Zamia cone, is 

 undoubtedly a Sequoia cone and not that of a species of Zamites. 



Zamites tenuinervis occurs in the Patuxent and Patapsco formations 

 in the Maryland- Virginia area, but it is especially characteristic of the 

 Patuxent. Elsewhere it occurs with considerable frequency in the Glen 

 Eose beds of Texas. It is also reported from both the EjQOx^dlle and 

 the Horsetown beds of California and from the Lower Cr^etaceous of the 

 Queen Charlotte Islands. It shows a striking resemblance amounting 

 almost to identity to Zamites Carruthersi Seward,^ from the English 

 Wealden. 



A number of preparations were made for the purpose of observing the 

 outlines of the epidermal cells and the stomata; but these all proved 



^ Seward, Wealden Fl., pt. ii, 1895, p. 86, pi. vi, figs. 2-4. 



