TYPE-SPECIMENS OF FOSSIL VERTEBRATES. 47 



580. Merychippus mirabilis Leidy. Paratype. 



Portion of right maxillary containing four teeth p 4 -m 3 . 

 Loup Fork (Upper Miocene). Niobrara River, 

 Nebraska. 



Leidy, Proc. Acad. Nat. Sci. Phila., 1858, p. 27; Journ. Acad. Nat. 

 Sci. Phila. (2), VII, 1869, p. 299, pi. 17, figs. 8, 9. 



= Protohippus mirabilis. 



571. Merychippus mirabilis Leidy. Plesiotypes. 



572. (1) Last right upper molar, m 3 ; (2) last upper molar of left 



581. side; (3) two upper premolars of right side, p 2 and p 3 ; 



582. (4) right upper premolar, p 2 . Loup Fork (Upper 

 Miocene). Niobrara River, Nebraska. 



Leidy, Journ. Acad. Nat. Sci. Phila. (2), VII, 1869, p. 299, (1) pi. 

 18, fig- 55; (2) fig. 56; (3) pl. 17, fig- 14; (4) fig- 15- 



= Protohippus mirabilis. 



2574. [Merychippus sp. undet.] 



Fragment of right lower jaw with five teeth, p 3 -m 3 . Middle 

 Miocene. Pojuaque, New Mexico. 



Cope, Rept. U. S. Geogr. Surv. W. 100th Merid., IV, Pt. II, 1877, pl. 

 75, figs. 4, 5 (unnamed). 



[Identified by J. W. Gidley.] 



120. Merychyus elegans Leidy. Cotypes. 



121. Right and left upper and lower jaws containing almost 



complete dentition. Loup Fork (Upper Miocene). 

 Niobrara River, Nebraska. 



Leidy, Proc. Acad. Nat. Sci. Phila., 1858, p. 25; Journ. Acad. Nat. 

 Sci. Phila. (2), VII, 1869, pp. 118, 380, pl. 11, figs. 1-11. 



439. Merychyus major Leidy. Type. 



Part of right upper jaw containing third and fourth premo- 

 lars and first and second molar. Loup Fork (Upper 

 Miocene). Niobrara River, Nebraska. 



Leidy, Proc. Acad. Nat. Sci. Phila., 1858, p. 26; Journ. Acad. Nat. 

 Sci. Phila. (2), VII, 1869, pp. 121, 380, pl. 11, figs. 15, 16. 



118. Merychyus medius Leidy. Type. 



Fragment of left side of lower jaw containing three molars. 

 Loup Fork (Upper Miocene). Niobrara River, 

 Nebraska. 



Leidy, Proc. Acad. Nat. Sci. Phila., 1858, p. 26; Journ. Acad. Nat. 

 Sci. Phila. (2), VII, 1869, pp. 119, 121, 380, pl. 11, figs. 12-14. 



156. Merycochcerus proprius Leidy. Type. 



Upper and lower jaws containing nearly complete dentition. 

 Lower Miocene. Near Fort Laramie, Niobrara River, 

 Wyoming. 



Leidy, Proc. Acad. Nat. Sci. Phila., 1858, p. 24; Journ. Acad. Nat. 

 Sci. Phila. (2), VII, 1869, pp. no, 380, pl. 10, figs. 1-4. 



445. Merycochcerus proprius Leidy. Paratype. 



Last left upper molar. Lower Miocene. Near Fort Lara- 

 mie, Niobrara River, Wyoming. 



Leidy, Proc. Acad. Nat. Sci. Phila., 1858, p. 24; Journ. Acad. Nat, 

 Sci. Phila. (2), VII, 1869, pp. no, 380, pl. 10, fig. 5. 



