744 GEOLOGY OF THE YELLOWSTONE NATIONAL PARK. 



present I am unable to suggest a closer atlinity. They have the same size, 

 shape, and approximately the same nervation as G. pJatanifoVta Ward,-' from 

 the Fort Union group, differing, however, in not having a toothed margin. 

 Professor Ward writes that the specimen upon which liis species was 

 founded is quite obscure, and it is possible that they may really l)e nearer 

 alike than ajjpears from the drawings. Additional material is needed to 

 fix their status. 



I have ventured to call this a new species, and liave named it in honor 

 of Mr. E. C. Alderson, wlio accompanied the expedition on which it was 

 obtained and assisted in making the collections. 



Habitat: Specimen Kidge, opposite mouth of Slough Creek and near 

 head of Crystal Ci'eek; collected by Ward and Knowlton, August, 1887. 



ARALIA(EiE. 



Arali.v wkightii u. sp. 

 PI. 01, tio. 1. 



Leaf firm, coriaceous, narrow in general outline, palmately 3 (possi 

 bly 5) lobed; central lobe largest, long, ovate-lanceolate, slender-pointed; 

 lateral lobes slender-lanceolate, half the length of the central lobe; all 

 margins perfectly entire ; basal portion of leaf unknown: in-imar}- nervation 

 palmate; middle lobe ^\ith a pair of opposite nerves nearl}- at right angles 

 to the midrib, which pass to the sinus, those above with about 10 jjairs of 

 alternate camptodrome secondaries, which are much curved u])ward and 

 arched along near the margin; intermediate secondaries occasional; lateral 

 lobes with a strong midrib and about 8 pairs of alternate or subopposite 

 nmch-arched camptodrome secondaries; finer nervation consisting of very 

 fine quadrangular arcolatiun. 



Tliis verj' peculiar species is unfortunately represented by only the 

 fragmentarv leaf figured. Tlie basal ])ortion is entirely destroyed and 

 it is therefore impossible to determine whether there were 5 or only 3 

 lobes. There is some evidence in favor of its having Ijeen r)-lobed. The 

 sinuses separating the lobes are somewliat rounded. The central l()lie is 

 \evx nmcli the larger. From the sinus it has (i cm. preserved and nmst 

 have been 8 cm. or more in length wdien entire. In the broadest part, 



'Types of the Larainie FL, ]). S9, I'l. XL, fis. 1. 



