7. GALEORHINID^ MUSTKLUS. 
19 
sixty species; found in all seas. {Carchariidcc part {Carchariina and 
Mustelina) Gunther, viii, 357-380, and 383-388.) 
* Teeth Hat aud paved, without cusps or cutting edges ; spiracles i)resent. ( Mustelince . ) 
fl. No pit at the root of the tail; labial folds well developed Mustelus 14. 
** Teeth more or less compressed, with entire or serrate sharp edges. (Galeorhinincf:.) 
b. Spiracles present. 
c. No pit at the root of the tail. 
d. Teeth small, each with a median cusp and one or two small lateral cusjis 
on each side Triacis, 15. 
dd. Teeth larger, with a single cusp, oblique, notched and serrated, 
Galeorhinu.s, 16. 
cc. A pit at the root of the tail ; teeth all serrate ; caudal liii with a double 
notch Galeocerdo, 17. 
bb. Spiracles obsolete. 
e. Teeth serrate, more or le.ss (entire in the very young or very old) ; little 
oblique or nearly upright. 
/. Teeth well serrated (in the adult) ; those of the upper jaw compara- 
tively broad or triangular; those of the lower narrow and elaviform, 
Carcharixus, 18. 
ff. Teeth scarcelj' serrated, constricted at base, narrow, clavifoi'iu, and 
straight in both jaws I.sogomphodox, 19. 
ee. Teeth all entire. 
g. Teeth nearly upright, the points not much directed towards the 
sides Aprionodox, 20. 
gg. Teeth oblique aud flat, the points turned to the right or left away 
from the centre, so that the inner margins are nearly horizontal and 
present a cutting edge Scoliodox, 21. 
14.— I?IUSTEI.US Cuvier, 1817. 
[Ho and 8 harlcs . ) 
(Bellon, Cuvier, Regue Animal: type Muntelus vulgaris M. & H. ) 
Body elongate, slender, not elevated ; snout comparatively long and 
flattened; mouth crescent-shaped, with well -developed labial folds; 
teeth small, many-rowed, flat and smooth, rhombic, arranged like pave- 
ment, alike in both jaws; eyes large, oblong; spiracles small, just be- 
hind the eyes ; pectoral tins large ; tirst dorsal large, not much behind 
pectorals; second dorsal somewhat smaller; anal opposite second dorsal 
and still smaller ; ventrals well developed ; basal lobe of caudal almost 
obsolete ; embryo not attached to uterus by a i)lacenta. Small sharks, 
tbe smallest of the American species, known at once by the smooth, 
paved teeth. (Latin, miifitela, a weasel or martin; the use of the word 
similar to that of yaz-iri, ya).eo~.) 
19. in. liisiBllllus (Blainv. ) J. & G. — Smooth Hound ; Dog Sharh . — Eniissole. 
Body slender, tapering backward from the dorsal fin to the long 
slender tail ; snout depressed, moderately sharp ; mouth small, the teeth 
all alike, a fold at the angle of the mouth ; first dorsal rather large, 
