Holt and Caldeewood — Report on the Rarer Fishes. 377 



Eye. — The emerald green pupil is very large, and in the fresh condition is the 

 more conspicuous, since a great part of the black iris is hidden by a folding-in of 

 the skin of the head. 



Labial folds extend from the angles of the jaw for about one-third of the length 

 of each side of the upper jaw, and are consequently somewhat widely separate 

 from each other in the middle line. 



Teeth in three vertical rows in upper, and two rows in under jaw. In the upper 

 jaw the middle, in the under jaw the inner row appear to be chiefly functional. 

 In the upper jaw there are 35 teeth in each transverse 

 row, i. e. 17 on each side of a median tooth. In the 

 under jaw there are 29 teeth in each row, 14 on 

 each side of a median tooth. The annexed woodcut 

 represents the central region of the mouth, seen 

 from the ventral aspect. In this the median teeth 



are distinctly visible. Central region of jaws of Centrophoriis 



The presence of the median teeth in this speci- mamosus. 



men is of some interest, since the dentition, in other respects, is completely 

 characteristic of the variety, as referred to above. 



Anatomy. — Of the visceral anatomy it may be remarked that it does not differ 

 in any essential degree from the familiar littoral Selachian type. Moreover, 

 Gtinther's description (" ChalL," vol. xxii., p. 6) of the viscera of the Japanese 

 C. squamulosus reveals an arrangement so much like the condition seen in our own 

 example that one description might do for both, except for the fact that the 

 specimen described by Giinther was a ripe female, 27 inches long, whereas that 

 now under consideration is a mature, but unripe male. 



The testes are of equal size, situated on a level with the first dorsal fin, white 

 in colour, and typically reniform in arrangement. 



Colour. — When first brought to the surface our specimen was of a uniform 

 chalky-whiteness, but shortly became darker, assuming a pale-leaden hue. The 

 difference between such and the blackish-grey colour stated by Vaillant to 

 characterize the variety seems unimportant, as it is evidently more the result of 

 a greater or lesser degree of expansion of similar chromatophores than of any 

 other distinction. In colouration, therefore, we may say that our specimen 

 conforms to the variety rather than to the type. An attempt, in fig. I, to 

 reproduce on so small a scale something of the velvety appearance of the skin 

 has resulted in making the fish look somewhat darker than it was in the living 

 condition. The action of alcohol has now caused a dull-brown colouration of the 

 skin, whilst, of course, the vivid green of the ciystalline lens has entirely disappeared. 



Locality and Disteibution. — Only one specimen was taken on a long line on 

 May 24th, 1891, at a depth of 250 fathoms, 45 miles off Blackrock, Co. Mayo. 



TEANS. EOT. DUB. SOC, N.S. VOL. V., PABT IX. 3 I 



