286 J.D. OGILBY AND A. RB. McCULLOCH. 
Synchismus, Gill, Ann, Mus. Nat. Hist. New York, 1861, p. 408 
(tuberculatus = indicus ) 
Body elongate and slender, the distal portion of the tail 
scarcely elevated above the axial plane. Scales minute 
and feebly unicarinate; lateral line inconspicuous. Head 
small, narrow, not depressed, with short and broadly 
rounded snout. Nasal valve folded, with a short cirrus. 
Mouth inferior, transverse, small, and much nearer to the 
tip of the snout than to the eye. Lower lip not divided by 
a symphysial groove. Teeth similar in both jaws, small 
and tricuspid, and arranged in many series. Spiracles 
large, below and partly behind the eye. Posterior gill-slit 
widest; three above the pectoral. Tail once anda half to 
twice as long as the head and trunk. First dorsal fin 
inserted wholly behind the base of the ventrals, subequal 
in size to the second. Anal fin low, inserted far behind 
the second dorsal, close to and overlapping the caudal, 
which is short; (xerAos, a lip; oxvAdAcov, seylliwm). 
Small oviparous ground sharks inhabiting the Indo-Pacific, 
Hemiscyllium, Muller and Henle, is considered by some 
authors to differ from Chiloscyllium in having the lower 
labial fold continuous across the symphysis of the lower jaw 
instead of being interrupted, and in having a longer tail. 
Specimens of both genera examined by us show some vari- 
ation in the former character, and as we do not think that 
the length of the tail alone can maintain the genus, we 
follow Regan in treating it as asynonym of Chiloscyllium. 
Key to the Australian species. 
a. Tail once and a half as long as the head and trunk; no 
ocellus above the pectoral fin punctatum. 
aa. Tail twice as long as the head and trunk; a large 
ocellus above the pectoral fin. 
b. Body with large scattered dark spots  ocellatwm. 
bb. Body with numerous small close set dark spots 
trispeculare. 
