92 THAR FLORA OF THE AMBOY CLAYS. 
similar habit. In a few the leaves are orbicular or slightly emarginate, 
but they are generally bilobed, the sinus reaching the middle of the leaf, 
sometimes extending to the base, as is the case with the only species 
inhabiting the United States, B. lanarioides Gray of Texas and Mexico. 
In most of the East India species the nervation is more crowded than 
in the fossil leaves before us, each nerve having three and sometimes four 
lateral nerves, the medial nerve, however, being quite the same. In several 
oriental species, and all those of the New World, the nervation is simpler 
and especially like that of the fossil. In the Texan species the leaves are 
generally divided to the base, and the medial nerve is therefore obsolete; 
the lateral nervation is, however, precisely that of our fossil. As the depth 
of the sinus is a variable character, differing greatly in the leaves of the 
same tree, it is quite possible that Bauhinia lunarioides is only a dwarfed 
and slightly modified descendant of the Cretaceous species. 
Prof. Oswald Heer, in his Flora Fossilis Arctica, Vol. VII, p. 45, Pl. 
LX, fig. 4a, describes and figures, under the name Diphyllites membranaceus, 
a bilobed leaf which in general form is much like those I have called 
Bauhinia cretacea, but the nervation as given by Heer is quite different. 
The leaf is divided to within an inch of the base, and a slender nerve, 
which would be the midrib in an ovate or lanceolate leaf, reaches nearly 
to the sinus, there forking symmetrically, the branches running near the 
margins of the sinus on either side. So far we have the nervation of 
Bauhinia, but in Heer’s Diphyllites the lobes of the leaf are traversed by 
a number of lateral nerves that spring from the base. Only one specimen 
seems to have been seen, but I strongly suspect that when others shall be 
obtained in a better state of preservation the nervation will be found to be 
different from that figured by Heer, and that his bilobed leaf will prove 
to be generically if not specifically identical with those which we have in 
the Amboy Clays. 
Velenovsky has described, in the Flora der Bbhmischen Kreideforma- 
tion, Part IV, Vol. V, p. 12, a bilobed leaf which is almost certainly a 
species of Bauhinia. The specimen figured by Velenovsky, like Heer’s 
Diphyllites, seems to be as yet unique, and it is also evidently malformed. 
One of the lobes is nearly complete, and in form and nervation practically 
