1884.] l"* [Cope. 



Twelfth Contribution to the Herpstology of Tropical America. 

 By E. D. Cope. 



{^Read before the American Philosophical Society, Bee. 19, ISS4.) 



I. On a Collection of Fishes and Reptiles from Monterey, Nuevo 

 Leon, Mexico. 



The following list represents a collection which I made when on a visit 

 to Monterey, in the month of November, 1883. The locality is an im- 

 portant one from the point of view of geographical distribution, as it is on 

 the borders of the two great realms, the neotropical and the uearctic. 

 How well it expresses this position may be seen from the accompanying 

 identifications. 



Pisces. 



Amiurus olivaris Raf., a large specimen obtained in a fresh state, from 

 the Salado river. 



Campostoma formosulum Girard. 



Htbognathus civilis, sp. nov. 



Scales 6-41-4 ; Radii ; D. I. 8 ; A. I. 8. Length of head equal depth of 

 body, and contained in the total length (including caudal fin) 5.25 times. 

 Eye contained 3.66 times in length of head, and 1.25 times in interorbital 

 width ; its form oval. The muzzle is obtuse at the extremity, and over- 

 hangs a little the premaxillary border. The mouth is small and horizontal, 

 and the lips are not sharp-edged. The extremity of the maxillary bone is 

 opposite the anterior nareal opening, not reaching the orbit by some dis- 

 tance. Infraorbital bones narrow. Frontal region convex transversely, 

 with two rows of tubercles on each side of a smooth median space in the 

 males ; the two interior rows coming together on the middle line on the 

 top of the muzzle. The rays of the pectoral fin are thickened in the 

 male, and they do not reach the ventrals. The ventrals do not reach the 

 vent, and their anterior origin is a very little in front of the anterior origin 

 of the dorsal fin. The gular isthmus is wide. 



Total length, .078 ; do. to opercular border, .010 ; do. opposite base of 

 dorsal, .032 ; do. to opposite base of anal, .044 ; do. to base of caudal, .065. 



Color, dusky above ; below silvery with dusky shades ; fins yellow at 

 the base, unspotted. 



This species is very abundant in the creek that rises in a large spring in 

 the city of Monterey. Its nearest relative is the H. flavipinnis Cope from 

 Western Texas. The latter differs in the larger eye, which enters the head 

 2.66 times, and equals the interorbital space, which is flat and not convex. 

 There is also a distinct lateral baud in the Texan species, which is in the 

 H. civilis only faintly indicated. The characters are constaut in small as 

 in large specimens. 



