494 Systematic Paleontology 



near Brooke, Virginia. As here recognized it embraces certain 

 apparently identical forms which were the basis for Protecephyllum 

 dentatum Fontaine, but which have no observable characters in common 

 with the species of that genus. They may be compared with various 

 supposed, but not true, species of Protorhipis. 



Occurrence. — Patapsco FoRMATioisr. Federal Hill (Baltimore), 

 Maryland; near Brooke, Virginia. 



Collection. — U. S. National Museum. 



Genus PROTEAEPHYLLUM Fontaine 

 [Mon. U. S. Geol. Survey, vol. xv, 1890, p. 281] 



This genus was established by Fontaine in 1890 for certain remains 

 of supposed primitive angiosperms and eight species, so-called, were 

 included in it. Since that date the same author has described several 

 additional species, also of nominal value. The original discussion which 

 is reproduced in the present connection for the sake of completeness 

 is as follows: 



" I group under this head a number of leaves with a very archaic 

 type of nervation that occur in the Potomac flora. In their nervation, 

 and in many eases in the form of the leaves, they bear a greater resem- 

 blance to species of Protea than any other plants. The main points that 

 characterize them are the absence of any pronounced difference in the 

 size of the primary nerves, the great slenderness of these, the lax and 

 irregular reticulation formed, and the uniformly strong ultimate nerves, 

 which gives a reticulation that reminds one of ferns. Indeed, I was 

 for some time in doubt whether some of these leaves were really angio- 

 sperms and not ferns. There are two types of these leaves, that differ 

 only in the presence or the absence of a distinct midrib; when the 

 midrib is present the leaves assume an elliptical form; when it is 

 absent, they tend to take an orbicular shape. We might perhaps divide 

 the genus into two subgenera according to this distinction, giving one 

 the name rotundatum and the other the appellation elongaium. 



" The genus may be described as follows : Leaves orbicular or elongate 

 in form; in the case of the former, no midrib present; in the case of 



