108 



rated it under a new genus, whose characters are those of the species. The 

 substance of the leaf is membranaceous, its surface smooth, the veins distinct, 

 and the areolation recognizable near the middle part, where it is mrkaed as 

 it is seen with the glass. The enlarged figure of the borders underneath 

 show the foliaceous appendages of the teeth ; some of them are curved 

 downward, and appear obtuse aud truncate. 



Habitat. — Near Decatur, Nebraska, a single specimen, Hayden. 



Frangidacece. 

 Paliurus membranaceus, Lesqx., PI. xx, Fig. 6. 



Leaf small, membranaceous, oval-obtuse, entire, palmately three-nerved from the base; lateral 

 nerves thin ; nervilles distinct, perpendicular to the nerves aud joining them. 



Paliurus membranaceus, Lesqx., American Journal of Science and Arts, loc. 



cit., p. 101. 



The only leaf by which this species is represented is of a thickish mem- 

 branaceous substance, with a polished surface ; oval, very obtuse, rounded to 

 the base by a less obtuse curve, with a comparatively thick medial nerve 

 ascending to the upper border of the leaf, and two thin lateral veins going up 

 from the base to two-thirds of the leaf in an acute angle of divergence of 20°. 

 The middle nerve is branching in its upper part; the lateral ones are also 

 branching outside ; all the subdivisions are simple, slender, on a broad angle 

 of divergence, most resembling the nervilles, which, from the middle of the 

 leaf downward, join the middle nerve to the secondary ones. The leaf (4£ 

 centimeters long and 3 centimeters wide) is apparently petioled, its base 

 curving down as slightly decurring to a broken petiole. 



From the numerous Tertiary species of Paliurus, to which this one 

 is comparable by its nervation, it differs especially by its very obtuse leaf. 

 Zizyijhus protolotus, (Ung., in Heer, Fl. Tert. Helv., Ill, p. 74, PI. cliv, Fig. 

 32,) represents, however, a still more round-obtuse leaf, but different in the 

 type of its nervation. 



Habitat. — Near Decatur, Nebraska, Hayden. 



Celastrophyllum ensifolium, Lesqx., PI. xxi, Figs. 2, 3. 



Leaves coriaceous, very thick, linear, abruptly narrowed to the base by a round curve, broadly 

 deltoid-pointed ; medial nerve very thick ; secondary veins thin, close, parallel, open, camptodrome. 



Magnolia ensifolia, Lesqx., Hayden's Report, 1871, p. 302. 



The species is represented by two leaves, one 12 centimeters long and 

 6 centimeters wide, and the other only 8£ centimeters long and 3J centime- 



