On some Fishes from the Irish Atlantic Slope. 279 



XXXV. — PreJiminary Note on some Fishes from the Irish 

 Atlantic Slope. By E. W. L. HoLT and L. W. Byrnb. 



These fislies were collected by Messrs. Farran and Keiup ia 

 the ' Helga ' in August 1908. 



Scylliorhinus indicus, Brauer. 



A young example, S. R. 593, 6/8/08, 50" 31' N., 11° 31' \V., 

 670-770 fathoms. 



We are indebted to Mr. Regan for the determination. The 

 species is otiierwise known only fro n the Pacific. 



Rhinochimrera atlantica, sp. n. 



An adult male, measuring 850 ram. to the origin of the 

 dorsal lobe of the caudal, and 1165 mm. in total length, 

 including the caudal filament. S. R. 593. 



Diagnosis. — Adult male with the snout (measured between 

 verticals from its tip to the origin of the vomerine dental 

 plates) as long as the distance between the dorsal insertions 

 of the pectoral and ventral fins and somewhat longer than 

 the base of the second dorsal fin. Second dorsal fin with base 

 about half as long as the distance between the gill-openings 

 and the origin of the ventral lobe of the caudal fin. Posterior 

 ventral claspers terminating in subconical slightly volute 

 clubs. Vomerine dental plates deeply notched on their 

 cutting-edges. 



The above characters, especially the relative shortness of 

 the base of the second dorsal fin, serve to distinguish adult 

 B. atluntica from adults of the very closely allied R. pacifica 

 (Mitsukuri). Nothing is known of the young of either 

 species. Harriotta ruleighana, Goode and Bean, known 

 only from immature specimens, is stated to exhibit a pro- 

 gressive developn)ent of tritoral elements on the dental 

 plates. In the absence of any evidence of the condition of 

 the plates in young and half-grown Hhinochimcera, in the 

 adults of which there are no tritors, it is unsafe to argue that 

 Rhinochimoira is the adult of Harriotta, which in respect of 

 other characters seems possible er.ough. 



Messrs. Farran and Kemp have collected five egg-purses 

 (between 550 and 720 fathoms) which appear to be identical 

 with those obtained on the American side of the Atlantic and 

 tentatively assigned to Harriotta. They closely resemble but 

 are much smaller than the egg- purse of R. pacifica^ which is 



