APPENDIX. 01 



pair being thinner and more like marginal veins than like primary nerves. 

 For this reason the lobes are not distinct, or scarcely more prominent than 

 the obtuse large teeth of the borders. By this character this leaf corresponds 

 partly to the first of the subdivisions established by Heer in this description, 

 leaves as broad as long, short-lobed, broadly obtusely dentate, and partly to 

 the fourth division, wherein he includes truncate or sub-truncate leaves. 

 The identification of this finely preserved leaf is positive. 



The relation of this species is with the present North American Acer 

 spicatum, the mountain Maple, whose range in the Northern States is from 

 the Atlantic to the Mississippi. 



Acer, species. 



The specimen shows only the middle part of a leaf. It is trilobed, the 

 lobes separated hij deep narrow obtuse sinuses; coarsely sinuate dentate on 

 the borders. As far as the characters are recognizable, the fragment repre- 

 sents a leaf equally referable to Acer macrophyllum, Pursh, and to Acer 

 grandidentatum, Nutt. It is intermediate in size, but comes nearer the last 

 of these species, especially similar to a large form of A. grandidentatum, 

 which 1 collected in the Ogden Canon of Utah. 



It is to be regretted that the fragment is not in a better state of preserva- 

 tion, and that it cannot be ascertained if this leaf of the Pliocene does not 

 positively represent a species intermediate between A. macrophyllum and A. 

 grandidentatum, or an older type, modified by peculiar circumstances forcing- 

 it to migrations, partly to the mountains where it became dwarfed, partly to 

 the south wherefrom it returned later and during the present period with 

 an amplitude of foliage resulting from a habitat in a warmer climate. 



Another specimen, No. 50, represents a large leaf, apparently referable to 

 Magnolia lanceolate/, p. 24, PI. VI. Fig. 4. 



The borders are erased, the nervation is obscure, the determination is not 

 certain. 



J ii .-i l"i of specimens, sent for examination by Professor William Denton, 1 found a few fragments of 

 leaves from the Chalk Bin lis, iii Nevada County. They represenl Quercus convexa, Lesqx., Aralia Zaddachi, 

 II eei, species already published from the same locality, ami an Acer, new for this flora. It is .1. sextianum, 

 Sap., a species found in France by the author, in the Gypses of Aix. then fore an eld type, at Ieasl Miocene 

 if not ohler.* The leaf i- three palmately nerved and palmate-trilobate; the medial lobe longer, and 

 sparingly dentate or minute-lobed ; but the lower part of the leaf is entire. In all its characters it seems 



* Saportti considers tin' formation as continuous from the upper Cretaceous to 1 1 j - lower Miocene. It has. how- 

 ever, a number of species identified in the Green River Group of the Rocky Mountains. 



