184 Trans. Acad. Sci. of St. Louis. 



and narrowed to the point; it is denticulate and becomes nar- 

 rower as it approaches the petiole which is four millimeters 

 long. The base is unequal and round. The primary nerve 

 is very strong ; the secondary nerves are prominent, alternate, 

 nearly straight, curving near the border, camptodrome, and 

 are connected with the points of the teeth by distinct veinlets ; 

 the tertiary nerves are very oblique and, as in many recent 

 species, nearly at right angles to the secondary ; nervilles dis- 

 tinct. These leaves belong, undoubtedly, to the Juglandaceae. 

 In the general character of the venation they agree with all 

 the figures with which they were compared. 



11. Juglans affinis, sp. nov. (Plate XIII. fig. 2). 

 Leaves lanceolate, acuminate, narrowed in a curve to a 



short petiole ; border serrulate ; lateral veins distant, alternate, 

 parallel, curved in passing to the borders, ascending high 

 along them in simple festoons, separated by short intermediate 

 tertiary veins; areolation irregularly quadrate. 



The above description corresponds almost entirely to that 

 of J. alkalina, Lesqx., the only essential difference being 

 in the kind of border. From the figure of J. alkalina, Lesqx. 

 (Hayden's Rept. 7. PL LXII. figs. 6-9), it appears that the 

 leaves must have had uniformly crenate margins, while the 

 present species shows distinct serrations. The figure repre- 

 sents the only leaf of the kind that came to my notice. The 

 leaf is nearly ten centimeters long and two and a half centimet- 

 ers broad. The nervation is distinct. In consequence of the 

 serrated border, the bows along the margin are connected 

 with the teeth by fine nervilles. 



ANACARDIACEAE. 



Rhus. 



12. Rhus rotundifolia, sp. nov. (Plate XII. fig. 2). 



Leaf trifoliolate (or odd-pinnate); leaflets orbiculate, ses- 

 sile; nervation looped; primary nerve strong; secondary 

 nerves curved in passing to the borders, camptodrome. 



Most of the plants belonging to this genus are characterized 

 by a strong nervation which varies much according to the 



