11. MUSTKLL'S. ySo 



terioi- flap. Tlie tirst dorsal fin is nearly iiiidway hotweon tlu- jioc- 

 torals and vcntrals; the second is not much smaller than the first, 

 and noai-ly entirely in advance of the aual. Ujjper parts wilh Mell- 

 definod black cross bands, narrower than the interspaces. A row of 

 rounded black spots along- the side of the body, alternating with the 

 dorsal cross l)ars. 

 Coasts of California. 



ft. Fine specimen (154 inches long). California. Purchased of the 



Godeffroy Museum. 

 b. Fine specimen, 27 inches long. San Francisco. Prcsent( d by 



Dr. W. (). Ayres. 

 c-g. Fnntus. ^fonterey. 



11. MUSTELUS*. 



Mustclus, Ciiv. lihjne Atii/n. 



The first dorsal fin opposite to the space between the pectorals and 

 ventrals, without spine ; the second not much smaller tiian the first. 

 No pit at the root of the caudal, which is without distinct lower 

 lobe. Membrana nictitans jiresent. Spiracles small, behind the eyes. 

 Mouth crescent-shai)cd, with well-developed, long labial folds. Teeth 

 small, numerous, similar in both jaws, arranged like pavement, ob- 

 tuse or with very indistinct cusps. « 



Temperate and tropical seas. 



1. Mustelus laevis. 



raXfos Xdos, Arigfof. Hist. Anim. vi. c. 10. 

 Galeus hiunulus, Bellon. De Aquat. p. 71. 



hevis, Rondel, p. 375. 



Squalus mustelus (part.), L. Syst. Nut. i. p. 400. 



Mustelus hevis, Risso, Etir. Meriil. iii. p. 127 ; Mull. S,- Henlo, p. 190, 



pi. 27. fig. 2 ; Midler, AbJiavdl. Ak. Jf'is.s. Bed. 18-10, p. 187, pi. 'i. 



tig. 1 ; Bumeril, Elasmohr. p. 401, pi. 3. tigs. 4-6 (teeth). 



punctulatus. Risso, I. r. p. 128. 



equestris, Bonap. Faun. Ital. Pcsce. 



Squalus mustelus, Bluinv. Faun. Frunq. Poiss. p. 81, pi. 20. fig. 1. 

 Mustelus mcgalopterus, Smith, III. Zool. South Afr. I'isc. pi. 2. 



vulgaris (part.), Miill. <^- Henle, p. 04. 



Pleuracromylon la3vis, Gill, I'roc. Ac. Nat. Sc. Philad. 18(34, p. 148. 



Embryo attached to the uterus by a placenta. Snout moderately 

 produced, the length of its jjrteoral portion being equal to the dis- 

 tance between the angles of the mouth. The posterior teeth in the 

 upper jaw are produced into an oblujue point ; sometimes another 

 minute cusp at the base besides. Origin of the dorsal fin nearly 

 opposite to the e.xtrenuty of the inner margin of the pectoral. Uni- 

 form greyish, or with small black spots. Hind margin of the caudal 

 fin generally blackish. 



As far as my ol)servations go, this is a more southern species than 



* 1. Mustehis piililbrnicus. GUI, Proc. Ac. Nat. Si-. Philad. 18C4, p. 148.— 

 San Francisco. 

 VOL. VIII. 2 c 



