FLORA OF THE DAKOTA GROUP. 87 



point. The whole surface is smooth with only some fragments of longi- 

 tudinal lines. 



No remains of Leguminosoe have been discovered in the Dakota Group 

 except the one figured as above. It appears to be a stipitatc legume with 

 analogy of form and size to those of Lonchocarpus, H. B. A; Kunth., a genus 

 mostly represented in the West Indian Islands, the equatorial America. 



GENERA AND SPECIES OF UNCERTAIN RELATION. 

 ASPIDIOPHYLLUM, Lesqx. 



Hav<len"s "Ann. Rep." 1874. p. 361. 



Leaves large, triangular in outline, palmately trilobate, truncate or rounded to 

 a peltate base; nervation coarse; primary nerves tritid, from a short distance above 

 the peltate base of the leaves, the lateral, at an open angle of divergence, son.etnnes 

 curved downward; secondary nerves generally close, parallel, camptodrome, generally 

 simple, joined by strong nervilles at right angles. 



This group has a great affinity by the form of the leaves and the 

 nervation to that of the Sassafras (Araliopsis). Indeed at first sight it 

 appears to differ from it only by the addition of a basilar shield. The 

 nervation, however, differs in some characters, the primary nerves being 

 at a more' open angle of divergentic, as are also the secondary ones, which 

 are also more curved in passing to the borders. The rounded more or less 

 enlarged shield of the base is nerved by the secondary nerves gradually 

 declining downward, one pair generally attached under the point of union 

 of the primary nerves, the others derived from the base of the medial 

 nerve and passing downward, the lowest nearly perpendicular in direc- 

 tion, and all abruptly curving and following the borders in continuous 

 flexures. The disposition of the lower lateral nerves has an analogy to 

 that of Oredneria, with the difference that in Credneria the lower secondary 

 nerves are all at right angles to the midrib. The same kind and degree of 

 analogy is marked between these leaves and those of Protophyllum and 

 Fterospermiies, and also those of Platanus. 



Aspidiophyllnni trilobatiim, Lesqx. 

 Plate XII, Fig. 1; XllI, Figs. 1-5; XIV, Fig. 1. 

 Leaves -enerally large, coriaceous, triangular or rhomboidal in outline, deeply 

 obtuse,;"rnobat" brivdly cu'neate to the base, enlarged into a half-round entire auncle 

 The leaves vary in size from 10 to 24 centimeters long and from 10 



