•b — 

 i 



Chologaster cornutus 

 niie FisK of the Dismal Sxtfamp 



W. W. WELSH, United States Bureau of Fisheries 



The first recorded description of this 

 curious and little-known fish was pub- 

 lished by the elder Agassiz in the Ameri- 

 can Journal of Science and Arts, in 1854. 

 The fish then described was taken in 

 ditches in the rice fields of South Caro- 

 lina. In 1853, on his return from a tour 

 through the Southern and Western 

 States, Professor Agassiz gave a sum- 

 mary of some of his ichthyological dis- 

 coveries in a letter to Professor J. B. 

 Dana. In this letter are the following 

 remarks : 



"I would mention foremost a new 

 genus which I shall call Chologaster, 

 very similar in general appearance to the 

 blind fish of the Mammoth Cave, though 

 provided with eyes ; it has, like Ambly- 

 opsis, the anal aperture far advanced 

 under the throat, but is entirely deprived 

 of ventral fins ; a very strange and unex- 

 pected combination of characters. I know 

 but one species, Ch. cornutus Ag. It is 

 a small fish, scarcely three inches long, 

 living in the ditches of the rice fields in 

 South Carolina. I derive its specific 

 name from the singular form of the 

 snout, which has two horn-like projec- 

 tions above." 



Since the discovery of this species by 

 Prof. Agassiz, two other species of 

 Chologaster have been described, both 

 being found in subterranean streams and 

 caves. 



The family to which Chologaster 

 cornutus is assigned, together with the 

 so-called blind-fishes, is the Amblyop- 

 sidse, composed of small, ovoviviparous 

 fishes living in caves, swamps and ditches 



of Southern and South Central States. In 

 this family the body is elongate, com- 

 pressed posteriorly, the head long and 

 flat, with projecting under jaw. Super- 

 ficially ther' is a strong resemblance to 

 the Poeciliidse, or Top Minnows, but the 

 mouth is smaller, the scales finer, the 

 ventral fins are absent or rudimentary, 

 and the vent is placed far forward. Of 

 the four or five known genera, the genus 

 Chologaster is the only one that has func- 

 tional eyes and a pigmented skin, all the 

 others having skin-covered eyes and col- 

 orless body. 



In Chologaster cornutus the ventral 

 fins are absent, and the vent is placed for- 

 ward of the pectoral fins. The body and 

 head are dark brown above, white below, 

 with three narrow longitudinal black 

 stripes on the sides, the middle one ex- 

 tending through the eye and snout. In 

 some examples the belly and sides of the 

 trunk are flushed with red of various 

 shades. The dorsal fin is white with dark 

 spots. There is a black blotch at the base 

 of the tail, beyond which is a white area 

 or bar; remainder of caudal dusky. The 

 length does not exceed two and one-half 

 inches. 



Cholgaster cornutus is found from 

 Virginia to Georgia, in swamps, ditches, 

 and backwater of small rivers. It ap- 

 pears to be solitary in habit, but is locally 

 abundant. In April, 1916, the writer ob- 

 tained six examples in the Little Peedee 

 River, all being captured in drifts of 

 dead leaves at the foot of sand-bars, and 

 in shallow indentations of the river bank. 

 Associated with them in such places were 



