372 Survey of Fishmg- Grounds, West Coast of Ireland, 1890—1891. 



Genus Centrophorus, Miiller and Henle. 



" Two dorsal fins, each with a spine, which is sometimes hidden below the 

 skin ; no anal fin. Trmik elongate, without lateral folds. Mouth wide, but 

 slightly arched ; a long, deep, straight, oblique groove on each side of the mouth. 

 Teeth of the lower jaw with the j^oint more or less inclined backwards or 

 outwards. Upj^er teeth erect, triangular, or narrow, lanceolate, with a single cusp. 

 No membrana nictitans ; spiracles wide, behind the eye. Gill openings narrow. ' 

 (Giinther.) 



Centrophorus squamosus, Gm., Linn. (Deep-sea.) 

 (PI. XLIII., 1, 1«, lb.) 



Centrophore ecaUieux, . 

 Sqiialus squamosus, 

 Centroscymnus ? squamosus ?, 

 Centroscymnus squamosus, . 



Macephilus dumerili, . 

 Centrophorus diimerilii, 

 Centrophorus squamosus, . 



5J 



)> 



3> 



Broussonet, "Mem. Acad. Sc," 1780, p. 675. 

 Gmel. Linn, vol. i., p. 1502. 



MuLLER & Henle, "Plagiostomen," p. 90. pi. xxxiv. 

 BocAGE & Capello, " Peix. Plagiost." ; " Proc. Zool. 



Soc. Lond.," 1864. 

 Johnson, "Proc. Zool. Soc. Lond.," 1867, p. 713 

 GiJNTHEE, " Cat. Fish. Brit. Mus.," vol. viii., p. 423. 

 GiJNTHER, " Cat. Fish. Brit. Mus.," vol. viii., p. 422. 

 Vaillant, " Exp. Sci. ' Travail.' ' Talism.' Poiss.," 



Paris, 1888, p. 75. 

 Holt, " Proc. Roy. Dub. Soc." vol. vii., p. 219. 



Remarks on the Synonomy. — We have followed Vaillant, the latest writer on 

 this species, in considering the forms described as C. squamosus and C. Dumerilii as 

 varieties of one species, since certain examples amongst those collected by the 

 "Talisman" and " Travailleur" are described as presenting a mixture of those 

 characters in virtue of which the s^jecies were originally separated. The matter 

 is treated at greater length below. 



Diagnosis of Species. — Scales, small and sessile on the snout and fins, larger, 

 pedunculate, and leaf -like, with posterior denticulations on the sides of the body ; 

 longer than broad, with a stout median keel projecting in front and behind, when 

 viewed superiorly : a lateral keel on each side, variable, may be strongly marked, 



