II. Mi'sTKHi*. ;<s;, 



terior Hap. The first dorsal tin is nearly midway bet\v<-C'U tlu; juo- 

 torals and ventrals ; the second is not much smaller than the hrst, 

 and nearly entirely in advance of the anal. Upper part.s wilh •well- 

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

 rounded black spots aloiio^ the side of the body, alternatini;- with tlio 

 dorsal cross bars. 

 Coasts of California. 



a. Fine specimen (34 inches long). California. J'urchased of tlie 



Godeffroy Museum. 

 h. Fine specimen, 27 inches long. San Francisco. l'resont(_d by 



Dr. W. (). Ayres. 

 c-g. Foetus. Monterey. 



11. MUSTELUS*. 



Mustt'lus, ('m: lih/ne Anim. 



The first dor.sal fin opposite to the space between the pectorals and 

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

 No pit at the root of the caiidal, which is without dislind lower 

 lobe. Membrana nictitans present. Spiracles small, Ixhiiid the eyes. 

 Mouth crescent-shai)ed, with well-developed, long labiiil folds. Tcet h 

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

 tuse or with very indistinct cusps. 



Temperate and tropical seas. 



1. Mustelus laevis. 



TaKfos Xetor, Aristot. Hist. Anim. vi. c. 10, 

 Galeus hiuuulus, Billon. l)t Aquat. p. 71. 



laevis, liondel. p. 875. 



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



Mustelus laivis, Hisso, Eur. Merid iii. p. 127; Miill. S,- I/etilr, p. HH). 



pi. 27. fig. 2 ; iMiiller, Ahhandl Ak. U'iss. Bed. 18J0, p. 187, pi. -'J. 



fig. 1 ; Dumeril, Elas»iohr. p. 401, pi. o. figs. 4-G (teeth). 



pimctidatus, Ri.-^so, I. c. p. 128. 



equestris, Bunop. Faun. Ital. I'cscc. 



Squalus mustelus, Blaiiiv. Faun. Fran^. Puins. p, 81, pi. 20. fig. 1. 

 Mustelus megalojiterus, iSinit/t, III. Zool. South Afr. Fisc. pi. 2. 



vulgaris (part.), Miill. Hf Ilvnle, p. G4. 



Pleuracroraylon IjBvis, Gill. Froc. Ac. Nat. Sc. FJiihul. ISC,}, p. ]4>. 



Embryo attached to the uterus Dy a placenta. Snout moderately 

 produced, the length of its praeoral portion ueing equal to the dis- 

 tance between the angles of the mouth. The i)osterior teeth in the 

 upper jaw are produced into an oblique point ; sometimes another 

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

 opposite to the extremity of the inner margin of the pectoral. Uni- 

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

 fin generally blackish. 



As far as my observations go, this is a more southern species than 



* 1. Mustelus niilitbi-uinis, GUI, J'roc. Ac. A'(//. .SV. P/iihid. 18G4, p. U8.— 

 Sau Frauoiscti. 

 VOL. VIII. 



