294 THE PLAGIOSTOMIA. 



Benthobatis. 



Benthobatis Alcock, 1898, Ann. mag. nat. hist., ser. 7, 2, p. 145. 



Disk little longer than broad, snout more than one third of the length. 

 Tail distinct, longer than the disk, with two dorsals and a well-developed caudal 

 and without lateral folds. Anterior nasal valves confluent in a quadrangular 

 flap, an upper lip. Mouth small, protractile. Teeth in bands as in Narcine. 

 Eyes small, rudimentary. Spiracles moderate, close behind the eyes. An 

 electric organ between the head and the pectoral. Skin smooth, soft. 



A deep-sea genus, allied to Narcine, from the Bay of Bengal. 



Eyes obsolete 



disk less than half the total length; no lateral folds on the tail 



body black moresbyi (page 294) 



disk half the total length; tail with lateral folds 



body fawn color; with spots of white . . marcida (page 295) 

 Eyes probably functional 



subcaudal and supracaudal equally developed 



body fawn color, with spots of white . . cervina (page 295) 



Benthobatis moresbyi. 



Benthobatis moresbyi Alcock, 1S98, Ann. mag. nat. hist., ser. 7, 2, p. 145; 1899, Cat. deep-sea fishes 

 Indian mus., p. 18; 1900, 111. zool. Investigator, pi. 26, f. 1. 



Disk subcircular, length more than width, more than one third preoral. 

 Tail longer than disk. Eyes rudimentary, obsolescent, unpigmented, optic 

 nerve slender. Mouth small, protractile; teeth bands narrow, of about ten 

 rows; each tooth acute angled inward, toward the mouth cleft. Gill openings 

 large, hindmost one nearer to vent than to mouth. Dorsals rather close to- 

 gether; first dorsal above hinder portions of ventrals. Ventrals distinct, rather 

 large, broad, outer angle blunt; claspers short, rounded, blunt. Skin smooth, 

 soft, purplish black, with scattered pores small and white over the disk and at 

 the edges. 



Specimens described, about fourteen inches in length, secured off the 

 Travancore Coast, in 430 fathoms. 



The published figure of this species makes it evident that the nearest ally 

 of the genus is Narcine, with which the rostral structure best agrees. Of the 



