<)0 Bulletin American Museum of Natural History. [Vol. XIX, 



is 2516. The describer concluded that the anal fin was absent 

 in the species, but the present writer finds no warrant in the 

 specimens for making any statements regarding this fin. The 

 length of the head, including the opercular apparatus, is con- 

 tained in the distance from the end of the operculum to the 

 beginning of the dorsal fin something over one and one-half 

 times. The head has not been prolonged into a beak such as 

 we find in the species of Leptotrachelus. 



Leptotrachelus longipinnis Cope. 

 Plate IV, Fig. 3, and Plate V, Fig. 4. 



Leptotrachelus longipinnis Cope (E. D.), Bull. U. S. Geol. and Geog. 

 Surv. Terrs. IV, 1878, p. 68. — Williston (S. W.), Kansas Univ. 

 Quart., VIII, 1899, p. 115; Univ. Geol. Surv. Kansas, VI, 1900, 

 p. 382. — Woodward (A. S.), Cat. Foss. Fishes, IV, 1901, p. 187. 

 — Hay (O. p.), Bibliog. and Cat. Foss. Vert. N. A. 1902, p. 397. 



Of this species Cope possessed two specimens. Of these 

 his "No. i" bears the Museum's catalogue number 2521 (PI. 

 V, Fig. 4) while his "No. 2" has the number 2520 (PI. IV, 

 Fig. 3). The former displays indistinctly the head, with its 

 long beak, the neck consisting of much elongated vertebrae, 

 the rays of the dorsal fin, and the ventral fins. Under a lens 

 traces of the pectoral fin may be found close to the head. 

 The other specimen shows more distinctly the dorsal and 

 ventral fins, and some ribs, triradiate scales, and longitudinally 

 directed hair-like bones in front of the dorsal. In No. 2521 

 a considerable part of the bones of the beak have been flaked 

 away, leaving only their impression on the matrix. The 

 letters sn indicate approximately the end of this beak. PI. 

 V, Fig. 4 shows the vertebrse of the neck forming a curve 

 at the left of the head. Above and at the left of this curve 

 is a blotch formed by the rays of another fish. 



Besides the American species, six others may be recognized, 

 as follows: L. armatus Marck and L. sagittatus Marck, from 

 the Upper Cretaceous of Westphalia, L. triqueter Pictet, L. 

 gracilis Davis, L. hakelensis Pictet and Humbert, all from the 



