70 BLIND VERTEBRATES AND THEIR EYES. 



THE AMBLYOPSID^:. 



The Amblyopsidae are a small family of fishes, first brought to the notice of 

 naturalists by W. T. Craige, who presented a specimen to the Philadelphia Academy 

 in 1842. De Kay, "Natural History of New York" (Reptiles and Fishes, p. 187, 

 1842), gives a brief description of AnMyopsis spclaus. It was followed at once by 

 articles by Wyman ( 1 843 and later, 1850, 1854 a and ft) and other articles by Thomp- 

 son (1844) and by Telkampf (1844). Renewed interest in the Amblyopsidae was 

 aroused by Agassiz's discovery of an epigean relative, Chologaster cornutus, in the 

 ditches of rice fields in South Carolina. 



Typhlichthys subterrancus was described by Girard in 1859 from a well near 

 Bowling Green, Kentucky ; Chologaster agassizii, by Putnam from a well at Leba- 

 non, Tennessee, in 1872; Chologaslcr papillifcnis, by Forbes in 1882. In 1898 the 

 present author described Typhlichthys rosa>, and a short time afterwards he 

 demonstrated that this species is generically distinct from Typhlichthys, naming 

 it Troglichthys. More recently (1905) he described Typhlichthys osborni and 

 Typhlichthys wyandotte. 



RELATIONSHIPS OF THE AMBLYOPSIDAE. 



The Amblyopsidae are members of the order Haplomi, first characterized by 

 Cope. 1 They have recently been defined by Boulenger, as follows : 



Air-bladder, if present, communicating with the digestive tract by a duct. Opercle well devel- 

 oped. Pectoral arch suspended from the skull; no mesochorochoid. Fins usually without, rarely 

 with a few spines; ventrals abdominal, if present. Anterior vertebrae distinct, without Weberian 



ii les. 



The order consists of a number of families of which the Galaxiidae and Aplochi- 

 tonida? are found in the fresh waters and occasionally in the oceans of the south 

 temperate zone; the Scopelidae are found pelagic and abysmal in the ocean, the 

 Kneriida.- in Africa, the Dalliidas in Alaska and Siberia, the Poeciliidse in fresh 

 water and along the shores of the tropical and temperate zones, and the Esocidae in 

 fresh waters of the north temperate zone. 



The Amblyopsidse are distinguished from the other families by the doubling 

 forward of the alimentary tract, the opening of the oviduct and anus being placed 

 close behind the throat, in front of the pectorals. 



The genera of the Amblyopsidae may be distinguished by the following char- 

 acters : 



a. \Vntral lni.|in i 'ill ; pylorii oiva 2 or 3 . . . . . . . Amblyopsis 



aa. Ventral fins absent 



"tic cceca 2 



i with cartilages Troglichthys 



cc. Sclcra witli Typhlichthys 



W>. Eye well <] ited; pvlnric coeca i ...... Chologaster 



1 1'ror. AUNT. Assoc. Adv. Si irmr, Indianapolis, i.Syj, }_>S and 333. 



