124 Zoology of Colorado 



anterior part of the body are conspicuously depressed. This is 

 an adaptive character, making it easier for the fish to live in swift 

 streams. In Discognathus, a genus of fishes found in mountain 

 streams of India, Ceylon and Abyssinia, there is actually a suc- 

 torial disc on the chin, whereby the fish can adhere to stones. 



Investigations are needed to ascertain how far up the moun- 

 tain streams our various Cyprinidae go. It was a matter for 

 surprise when Howell Ellis found the Black-headed minnow 

 (Pimephales promclas of Rafinesque) abundant in Glacier Lake, 

 Boulder County. It has also been found by F. M. Gaige in Bear 

 Creek Lake, a small lake without outlet or inlet, at 9,000 feet on 

 East Spanish Peak, as reported to me by Dr. Hubbs. This is a 

 herbivorous species, the breeding males conspicuous for the black 

 head. The length of the fish is three inches or somewhat over. 



The Killifishes or Poecilidae are represented in Colorado by 

 the genus Fundulus, with two species. The common name is 

 apparently derived from an old name for brook or creek, which 

 also survives in the word Catskill. The Zebra Fish (F. zebrinus 

 of Jordan and Gilbert), which abounds in the streams of Eastern 

 Colorado, is very easily known by the strong vertical dark bars 

 alternating with light ones, the squared-off tail, and the long 

 dorsal fin opposite the anal. The Little Red-fin (F. floripinnis 

 of Cope) has a similar tail, very broad at the base, but the 

 body is not barred. The fish is greenish or grayish-green, light 

 below, with the pectoral, ventral and anal fins yellow, with a 

 broad margin of bright red. This fish has been found in various 

 streams in the Platte basin. The type locality is Cherry Creek.* 



The common Eel (Anguilla rostrata of LeSueur) is reported 

 from the Rio Grande in Colorado, but when Ellis was preparing 

 his work on Colorado fishes, he could not obtain any specimens. 



We now come to the "higher" fishes, in which fin-rays are 

 partly spine-like, and the position of the pelvic or ventral fins 

 is far forward, near to or below the pectorals. The stiff spines 

 of the erectile dorsal fin must serve to prevent birds from swallow- 

 ing the fishes tail first, and allow a good many to escape. We 

 have three families of these advanced fishes, the Cottidae or 



*Dr. Hubbs thinks that F. floripinnis is a synonym F. sciadicus of Cope, described from 

 the Platte River in Nebraska. F. zebrinus he refers to Carman's genus Plancterus, as P. zebra 

 of Girard. He finds that there are two species involved; tho true P. zebra of the Rio Grande 

 basin, and P. kansae of Carman, the species inhabiting the rivers of our eastern plains. 



