EXPLANATION OF PLATES I. AND IT. 413 



No. 10. 



There are two good impressions of another cordate leaf, 

 which, instead of the smooth lamina of the preceding, have 

 the surface densely and equally covered with pores invi- 

 sible to the naked eye, and which may have been produced 

 by a close, stiffish pubescence. The outline of the leaf 

 has been exactly cordate with a short acuminated point, 

 and the base not so full as the preceding, but rather 

 reniform. The point has a perfectly even edge, and the 

 basal lobes are also quite entire ; but the rest of the mar- 

 gin, of which only a small part is quite complete, seems to 

 have been undulated, the projections not amounting to 

 teeth. A straight, tapering mid-rib gives off about seven 

 lateral branches on each side, at an angle of about 45°, not 

 exactly opposite, but so approximated as to form pairs. The 

 lowest pair rise more nearly opposite, but are not so much 

 more conspicuous than the others as to give a triple-ribbed 

 appearance to the leaf. Some of the lateral branches fork 

 near their tips ; they are all joined by transverse veins 

 similar to those of the preceding species, and the intervals 

 are filled up by less obvious reticulations. The lower 

 pair of lateral branches send ramifications downwards to 

 the basal lobes stronger than the ordinary connecting veins. 

 This leaf is about five inches in length, and of equal or su- 

 perior breadth. A small part of the footstalk only remains. 



No. 11. 



Another impression of a pennately-veined leaf presents 

 a distinctive character in the fine acute reticulating veins, 

 which are prominent in the cast of the under as well as 

 of the upper surface of the leaf. The areola? are flat, 

 but traversed also by minute winding prominent veinlets, 

 the ultimate reticulations being very minute. In the 

 general character of the principal veins, this species strongly 

 resembles No. 10. Of the outline, not much can be said, 



