162 THE FLORA OF THE DAKOTA GKOUl'. 



It is 3™ \onii; from tlit- top of the petiole to that of the median nerve and 

 nearly 5*"'" broad l)i't\veen the lateral, obtuse lobes, subemarginate by con- 

 traction of the huuiiui at the apices of the primary nerves. The petiole is 

 2"*" long; the secondaries, of which there are two pairs, are thin, opposite, 

 the upper ones corresponding to the intermediate, short, obtuse, subapicial 

 lc)bes. There is at the base a very thin, marginal nerve following the bor- 

 ders, with which lower, thin branches of the primaries, like nervilles, anas- 

 tomose, forming a continuous series of bows along the lower borders. 



Habitat: Ellsworth County, Kansas. No. 48 of the collection of the 

 University of Kansas; A. "Wellington, collector. 



CiSSITES POPULOIDES, sp. nOV. 



PI. XVIII, Fig. 12-14. 



Leaves thin, comparatively small, ovate or broadly cuneiform, subcor- 

 date at the base, obtuse, entire, long petioled; nervation subtripalmatifid 

 from the base; median nerve thick; lateral primaries thin, branching on the 

 under side, parallel to the secondaries, of which there are four or five pairs, 

 equidistant, opposite, simple or forking near the borders, sidjcraspedodrome. 



The leaves are from 2.5'"" to 4™ long and from 3""° to 3.5*"" broad, en- 

 larged above the base, rounded to the apex or oblong and obtuse, Avith a 

 petiole 1*"" long, appearing broken. The angle of divergence of the nerve 

 is 50°. 



This species has the peculiar nervation of the Cretaceous leaves referred 

 to Populites. The nervation is apparently tripalmate, but the primary lat- 

 eral nerves are quite thin, like the secondaries, and merely differ from them 

 by their position and their branches. The nervation is crasjiedodrome, but 

 the nerves, which are simple or forking near the borders, are not quite dis- 

 tinctly seen entering them, but vanishing to them as in species of Cissites. 



Habitat: Ten miles northeast of Delphos, Kansas. Nos. 4137 and 4183 

 of the collection of Mr. R. D. Lacoe. 



Cissites Bbownii Lesq. 

 PI. XVIII, Fig. 11. 



Geol. Eept. of Minnesota, by Prof. N. H. Winchell (unedited). 



Leaves coriaceous, oval, angularly undulate or sublobate, entire, obtuse 

 at apex; broadly cuneate at base and joining the petiole l)va short, inward 

 curve, jieuninerved. IVimary nerves straight, half cylindrical; secondaries 

 half open, alternate, parallel, rigid, scarcely curved in traversing the blade, 



