CARCHARIID^E. 295 



Genus IV Mustblus, Guvier. 



Pleuracromylon, Gill. 



Membrana nict it ans present. Small spiracles behind the eyes. Mouth crescentic, 

 with long labial folds. Teeth small, numerous, similar in both jaws, pavement -like, 

 obtuse, or with indistinct cusps. The first dorsal fin spineless, situated somewhat 

 behind the origin of the pectoral, or above the interspace between that fin and the 

 ventral: the second nearly as large as the first: caudal without a distinct lower 

 lobe, and no pit at the commencement of the fin. 



Two species of this genus are common off our coasts and inhabit the European 

 seas, the M. vulgaris, in which the young are developed without any placenta ; 

 and the M. Icevis, the embryo of which possesses a placenta attached to the walls of 

 the uterus. This latter form has not yet been observed on our shores, although 

 common in some of the European seas So long ago as the times of Aristotle and 

 Rondeletius the distinctive marks between thes3 two species were recognized ; 

 but subsequent to the time of Gesner they became overlooked, and the two 

 species were classed as one. At the commencement of this century Risso, and 

 subsequently others, ascertained the correctness of the opinion held by Aristotle. 

 The dorsal fin is placed somewhat more forward in M. vulgaris than it is in 

 M. Iwvis. 



1. Mustelus vulgaris, Plate CLV. 



Galeus asterias, Rondel, p. 376. Mustelus Icevis, Salv. p. 137, pi. xliv ; 

 "Willugh. Hist. Pise. lib. iii, c. xiii, p. 60, pi. B5, f. 2; Jonston, De Pise. p. 26, 

 t. viii, f. 6 ; Ray, Synopsis Pise. p. 22. Galeus stellaius, Gesner, 1598, p. 77, c. fig. 

 Squalus, Artedi, Gen. p. 66, Synom. p. 93. Smooth-hound or shark, Pennant, Brit. 

 Zool. (Ed. 1766) iii, p. 151, pi. xvi (Ed. 1812), iii, p. 151. 



Saualus mustelus, Bonnaterre, Enc. Ich. p. 7, pi. vii, f. 21 ; Lacep. i, p. 242 ; 

 Gmel. Linn. p. 1492 ; Bl. Schn. p. 128 ; Risso, Ich. Nice, p. 33 ; Turton, Brit. 

 Fauna, p. 112; Jenyns, Brit. Vert. p. 502; Johnston. Berwick. N. F. Club, 

 1838, i, p. 176; Schlegel, Dieren Neder. p. 190, pi. xviii, f. 2. 



? Mustelus stellatus, Risso, Eur. Merid. iii, p. 126. 



Galeorhinus hinnulus, Blainv. Fauna France, Poiss. p. 83, pi. xx, f. 2. 



Mustelus Icevis, Flem. Brit. An. p. 166; Templeton, Mag. 1ST. Hist. 1837 (2) 

 i, p. 413; Yarrell, Brit. Fishes (ed. 1) ii, p. 393, c. fig. (ed. 2) ii, p. 512; 

 Swainson, Fishes, ii, p. 316 ; Parnell, Wern. Mem. vii, p. 416 ; Thompson, N. H. 

 Ireland, iv, p. 252. 



Galeus mustelus, Leach, Wern. Mem. ii, p. 63, pi. ii, f. 3. 



Mustelus plebejius, Bonap. Faun. Ital. Pesc. iii, p. 43, t. f . 1 ; Giglioli, Catal. 

 Pesc. Ital. p. 51 ; Canestrini, Faun. Ital. Pesc. p. 49. 



Mustelus vulgaris, (pt.) Miiller and Henle, Plagiost. p. 190, pi. xxvii, f. 1 ; 

 Miiller, Abh. Ak. Wiss. Berlin, 1840, p. 187, pi. iii, f. 2 ; Yarrell, Brit. Fishes 

 (ed. 3) ii, p. 495, c. fig. ; Kroyer, Damn. Fisk. iii, p. 930 ; White, Catal. p. 127; 

 Dumeril, Ich. i, p. 400, pi. iii, f. 1-3 (teeth) ; Bocage and Capello, Peix. Plagiost. 

 p. 16 ; Gunther, Catal. viii, p. 386 ; Moreau, Poiss. de la France, i, p. 311. 



Smooth-hound, Couch, Fish. Brit. Isles, i, p. 47, pi. x. 



In form this fish considerably resembles the tope, Galeus vulgaris, but the snout 

 is not so much produced. Eyes rather large : oval. Nostrils one-third of the 

 distance between the anterior extremity of the mouth and the snout. Spiracles 

 small ; gill-openings rather short, the last three being over the base of the 

 pectoral. Teeth pavement-like, small and numerous. Fins the first dorsal 



