56 DESCRIPTION OF SPECIES. 



figured. It differs merely by the secondary nerves not being as thick. 

 The areolation is not distinct. 



SASSAFEAS, Nees. 



Sassafras Mudgei, Lesqx. 

 " U. S. Geol. Rep.," vi, p. 78, pi. xiv, figs. 3, 4 ; xxx, fig. 7. 



Sassafras acutilobum, Lesqx. 

 Plate V, Figs. 1, 5. 

 " IT. S. Geol. Rep.," vi, p. 79, pi. xiv, figs. 1, 2. 



The form appears specific, as it is represented by leaves of very differ- 

 ent size and always with the same characters. All the lobes are very 

 entire, the lateral either broadly diverging, sometimes nearly at right angles 

 to the midrib or erect; the venation is distinct but not coarse. The leaf, 

 fig. 5, is one of the smallest seen of this species. The largest measures 

 12 to 14 centimeters long without the petiole, or still more, for I have seen 

 from Kansas a fragment, only the middle lobe, 10 centimeters long from 

 the sinuses to the apex and 4 centimeters broad. As the lateral lobes 

 greatly vary in their divergence, of course the width of the leaves differ 

 much. The species is especially abundant at Thomson Greek, near Fort 

 Harker, with S. cretaceum and other forms of the same type. 



SASSAFRAS (Araliopsis), Lesqx. 

 Sassafras (Araliopsis; cretaceum, Newby. 



"Later Ext. El.," p. 14; "Illustr,"pl. vi, figs. 1, 4 (fragments of leaves). Lesqx., "U. S. Geol. Rep.," vi, p. 80, 

 pi. xi, figs. 1,2; xii, fig. 2. 



Sassafras (Araliopsis) obtusum, Lesqx. 

 5. cretaceum, var. obtusum, Lesqx., " U. S. Geol. Rep ," vi, p. 80, pi xii, fig. 3 ; xiii, fig. 1. 



This form should be considered as specific, not merely on account of 

 its shorter, more obtuse lobes, but particularly of the venation, which is 

 much coarser than in the preceding species. The primary nerves, espec- 

 ially, are much broader and sharply cut. It is found with S. cretaceum at 

 Thomson Creek; but it is also found by itself alone in other localities. 



Sassafras (Araliopsis) mirabile, Lesqx. 



" U. S. Geol. Rep.," vi, p. 80, pi. xii, fig. 1. 



Platanus latifoba, Newby., " Later Ext. Fl.," p. 23 ; " lllustr.," pi. ii, fig. 4. 



To the characters indicated in "Rep.," vi, may be added the thick 

 coriaceous substance of the leaves, which in small specimens appear 



