DESCRIPTION OF SPECIES— NYSSE^. 245 



closer, lateral veins, and oblique nervilles; they have, however, as seen in fig. 

 25, the upper part narrowed to an acumen or to a point. With Weber's 

 figure, our leaf agrees especially in its nervation, the lateral nerves being 

 curved alike iu passing toward the borders, and the nervilles, especially 

 distinct in their point of conjunction to the veins, being also in right angle to 

 them, and more distant than in the form described by Heer. The only 

 difference is in the narrower shape of the American leaf, more gradually 

 narrowed to the point, and less obtusely rounded to the base. This leaf is 

 ten centimeters long and four broad ; that represented in the Paiseontographica 

 is nearly at long and five and a half centimeters broad. Differences of size 

 for leaves of this genus cannot be taken into account for specification. 

 Habitat. — Near Point of Rocks, Wyoming* {Dr. F. V. Hayden). 



nyssej:. 



NYSSA, Limi. 



A genus exclusively North American at the present time, the only four 

 species known belonging to the flora of the eastern slojie of the United States. 

 It is, however, represented in the Miocene of Europe hy the fruits of ten 

 species, by the leaves of three others, and by five described as Nyssidium, 

 from seeds discovered in the same formation of Spitzbergen. This genus 

 seems to be a recent one, like the former; Prof Newberry's Nyssa vetusta 

 from the Cretaceous being, it seems, recognized by the author as a Magnolia. 

 The fruit and leaf described here are both from the Eocene of Golden, and 

 may represent one species only. 



Nyssa lanceolata, Lesqz. 



Plate XXXV, Figs. 5, 6. 

 Kytia lanoeolaia, Lesqs., Aunual Report, 1872, p. 407 (in description of fragments of leaves only). 



Leaf broadly lanceolate, rounded in narrowing to the base, with borders very entire; secondary 

 nerves inequidistaut, open, parallel, camptodrome; surface punctate. Fruit comparatively large, pre- 

 cisely ovate, round on one side, obtusely pointed on the other, deeply, distantly costate, and striate. 



The leaf is of thin, or rather membranaceous, consistence. Its size is 

 seven to eight centimeters in length, the point is broken, and four centimeters 

 broad below the middle; the lateral nerves diverge from the midrib at an 

 angle of 40° to 50*^, the two lower pairs being slightly more open, and not as 

 strongly formed as the upper ones, which generally branch once toward the 

 borders, which they closely follow in simple bows. The form and size of 



"The Camp Station, near Point of Rocks, has plants of the Washakie k"^"? No. ;!; that of Point 

 of Eocks Station is much lower, as remarked in the geological part of this work. 



