TLOEA OF THE DAKOTA GHOUP. 67 



opsis, and now as Cissifes, have indeed some characters which relate them 



to Araliopsis. They are palmately trilobate, have about the same form as 



Araliojjsis cretaceus var. ohfusus, and an analogous distribution of the 



nerves and secondary veins. They differ much by the thin texture of the 



leaves and the disposition of the lobes to become more or less obtusely 



and distinctly dentate at the apex, as seen by hgs. 2 and 4. The rapidly 



narrowed base and the very long petiole give to them a peculiar fan-like 



shape. Their relation to this group seems indicated by their affinity to 



Cissites insignis. 



Cissites Harkeriaiius, Lesqx. 



Plate III, FigB. 3, 4. 



Hayden'a "Ann. Rep.," 18T4, p. 352, pi. vii, figs. 1, 2. 



Sassafras (Araliopsis) Harkerianum, Lesqx., " U. S. Geol. Rep.," vi, p. 81, pi. xi, fig. 4. 



Leaves coriaceous, broadly rhomboidal in outline, and cuneate to the petiole, 

 p.ihnately sub-trilobed ; lateral primarj' veins joined at a short distance above the base; 

 secondary veins and their divisions camptodrome. 



The leaves figured here are smaller than fig. 4, pi. xi, of the "U. S. 



Geol. Rep.," vi; but this is the only difference, and a number of specimens 



have been found of leaves of intermediate size. The nervation is. of 



course, more or less pronounced, according to the face exposed upon the 



stone. The relation of this and the preceding species to Araliopsis is 



easily remarked. 



Cissites affinis, Lesqx. 



Platanus affinU, Lesqx., "U. S. Geol. Rep.," vi, p. 71, pi. iv, fig. 4; xi, fig. 3. 



Leaves coriaceous or sub-coriaceous, triple-nerved from near the base, sub-trilobate, 

 rounded in narrowing to the petiole, broadly deltoid to the apex; borders marked by 

 short distant teeth at the points of the excurreut nerves and their branches. 



Cissites acumiiia.tus, Lesqx. 

 Plate V, Figs. 3, 4. 

 Hayden's "Ann. Rep.," 1874, p. 353, pi. viii, fig. 1. 



Leaves deltoid from the middle to the acute point, rounded from the middle down- 

 ward to the petiole, triple-nerved from the base. 



These leaves, 7 to 8 centimeters long and nearly as broad, iiiiieh 



resemble those of the preceding species; they differ merely by the borders 



being entire, the secondary nerves more numerous and camptodrome. In 



fig. 4 the points of tlie lower pair of these lateral nerves reach Id the borders 



