LAMNID^. 303 



Genus III — Selache, Guvier. 



Cetorhinus, Blainville : Polyprosopus, Couct. 



Eye destitute of memhrana nictitans : a small spiracle between the eye and the 

 first gill-opening. Oill-openings very large. Gills furnished with gill-rakers 

 for filtering purposes, and consisting of an elastic apparatus of dentine. Teeth small, 

 conical, without dilated bases, and their sides smooth. First dorsal fin above the 

 interspace between the pectoral and the ventral: second dorsal and anal small. 

 Caudal with a lower lobe and a pit at its root : sides of the tail keeled. 



Geographical distribution. — From the Arctic seas and. North Atlantic to the 

 Mediterranean. 



On the gills of this fish are elastic appendages or gill-rakers (pi. clviii, f. la 

 and lb) consisting of dentine ;* so that each may, to a cex-tain extent, be regarded 

 as the analogue to an elongated and modified tooth. These act like the blades of 

 baleen in the mouth of the whalebone whale, as sifting organs serving to filter 

 the water passing through the gills, and thus enabling them to retain the small 

 marine organisms on which they subsist. This structure has attracted the notice 

 of many naturalists. Pennant, in 1776, observed that " within side the mouth, 

 towards the throat, was a very short sort of whalebone:" and Low, that its 

 gills were fringed with a sort of short bristles approaching the nature of 

 whalebone. In 1870 Mr. Cornish likewise alluded to this structure in one taken 

 at Penzance. Professor Steenstrup (Overs. Dan. Selsk. 1873, No. 1) gives an 

 account of these organs and their uses, as did also Professor Turner (Journ. 

 Anat. and Phy. April, 1880, xiv, pt. iii, p. 273) ; and it is observed that the 

 presence of bodies possessing the structural character of teeth or gills (as gill- 

 rakers) is not very aberrant, as they are not infrequent in osseous fishes, in 

 which there is a tendency for dental structures to spring from the mucous 

 membrane covering this part of the skeleton. Allusion to this sifting apparatus 

 has been omitted by Sir E. Home in his Memoir on this shark, also by Vrolik, 

 De Blainville, and others. Judging from the small size of its teeth, also the 

 large size of its gill-openings to permit the passage of a great amount of water, 

 and this sifting apparatus to detain minute structures, as well as what has 

 been obtained from its stomach after death, it would appear that this fish is not 

 a rapacious monster, but a devourer of minute animals and perhaps herbage. 



1. Selache maxima, Plate CLVIII, fig. 1. 



Squalus maximus, Gunner, Trond. Selsk. Skrift. 1765, iii, p. 33, t. ii, and iv, 

 p. 14, t. iii; Linn. Syst. Nat. (Ed. xii) i, p. 400; Gmel. Linn. p. 1498; Lacep. 

 i, p. 209 ; Bonnaterre, Ency. Ich. p. 10, pi. vii, f . xix ; Bl. Schn. p. 134 ; Turton, 

 p. 112 ; Plem. Brit. Anim. p. 164 ; Mitch. Lit. and Phil. Trans. New York, i, 

 p. 486 ; Schlegel, Dieren Neder. p. 191, pi. xix, f. 1. 



Bashing shark. Pennant, Brit. Zool. (Ed. 1776) iii, p. 101, pi. xiii (Ed. 1812) 

 iii, p. 134, pi. xvi ; Low, Fauna Oread, p. 171 ; Shaw, Zool. v, pt. (2) p. 327, 

 pi. cxlix (male) and 150 (female). 



Squalus peregrinus, Blainv. Ann. Mus. xviii, p. 88, pi. vi. 



Cetorhinus gunneri, homianus, et shavianus, Blainv. Bull. Soc. Phil. 1810, 

 p. 169. 



Selache maxima, Cuv. Regne Anim. 111. pi. cxv; Faber, Fisch. Isl. p. 10; 

 Yarrell, Brit. Fishes (ed. 1) ii, p. 396, c. fig. (ed. 2) ii, p. 518 (ed. 3) ii, p. 508 ; 

 Jenyns, p. 503 ; Templeton, M.N. Hist. 1837 (2) i, p. 413; Parnell, Wern. Mem. 

 vii. p. 418 ; Swainson, Fishes, ii, p. 314 ; Miiller and Henle, p. 71 ; Eichards. 



* E. P. Wright, Nature, August 10th, 1876. 



