92 Bulletin Amerkafi Museum of Natural History. [Vol. XIX, 



Most of Cope's measurements are taken from the type, but 

 the distance from the snout to the base of the ventral fins is 

 taken from No. 2513. This was necessary because in the 

 type the ventrals have been washed forward to beneath the 

 lower jaw, as may be seen from the figure. 



On the block containing No. 2523 are scratched in pencil 

 the words "Yankton, Neb." The other specimens are with- 

 out doubt from the same locality. 



Leptosomus lineatus {Cope). 



Plate IV, Fig. 6 and Plate V. Fig. 2. 



Sardinuis lineatus Cope (E. D.), Bull. U. S. Geol. and Geog. Surv. 

 Terrs. IV., 1878, p. 71. — Woodward (A. S.), Cat. Foss. Fishes, 

 IV, 1901, p. 248. — Hay (O. P.), Bibliog. and Cat. Foss. Vert. 

 N. A. 1902, p. 391. 



This species was based on two specimens. No. 2538 (PL 

 IV, Fig. 6) and No. 251 1 (PI. V, Fig. 2). The former specimen 

 displays the body as far back as the rear of the dorsal fin ; the 

 latter specimen shows the hinder half far enough forward to 

 show the tips of the ventral fins ; but neither specimen shows 

 both the dorsal and the ventrals. Hence, the exact relation 

 of these fins to each other can not be determined. 



The block on which No. 2538 is preserved, and which also 

 bears Spaniodon simus, is marked "Yankton, Neb." 



Leptosomus percrassus {Cope). 



Plate V, Fig. 3. 



Sardinius percrassus Cope (E. D.), Bull. U. S. Geol. and Geog. Surv. 

 Terrs. IV, 1878, p. 72. — Woodward (A. S.), Cat. Foss. Fishes, 

 IV, 1901, p. 248. — Hay (O. P.), Bibliog. and Cat. Foss. Vert. 

 N. A. 1902, p. 391. 



This species is represented by a single specimen, No. 2510 

 (PI. V, Fig. 3). It differs from the other species in having 

 a much deeper body. Although there is no record either on 

 the block bearing this species, or in Professor Cope's descrip- 

 tion, there can be do doubt that it came from the same 



