80 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



from mouth and snout tip, internarial equals preoral length, nasal 

 cirrus 1% in preoral length, not reaching lower labial groove; inter- 

 orbital 2% in head, mesially concave. First gill opening II/2 in eye, 

 1% in last gill opening. Spiracle subvertical, in deep, ovate, rimmed 

 pit, lyo in eye. 



First dorsal inserted above middle of ventral base, front and outer 

 edges sublinear and intervening angle broadly rounded, hind angle 

 pointed, fin base i/o more than vertical fin height ; second dorsal simi- 

 lar but smaller; anal height 2% its base, 1% in space to subcaudal; 

 caudal 4i/^ in total body length, subcaudal depth 6% in caudal ; pec- 

 toral obovate, 1^% in head; ventral origin little nearer first dorsal 

 than pectoral. 



Upper surfaces, sides and tail ashy gray. Lower surface of 

 head, throat, and abdomen white. Length, 457 mm. (Ogilby and 

 McCulloch.) 



Queensland. The type, No. 1965 in the Queensland Museum, from 

 Moreton Bay. 



Genus HEMISCYLLIUM Andrew Smith 



HemiscylUum Andrew Smith, Proc. Zool. Soc. London, 1837, p. 86. (Type, 

 Squalus ocellatus Bonnaterre, inouotypic. ) 



ChUoscylUnm Muixeb and Henle, Arch. Naturg., 1837, p. 395. (Atypic. Type, 

 Scyllium plagiosum Bennett, Syst. Beschr. Plagiostoraen, p. 17, 1841 : desig- 

 nated by Gill, Ann. Lyceum Nat. Hist. New York, vol. 7, p. 42, 1862.) 



SyncMsrmis Gill, Ann. Lyceum Nat. Hist., New York, vol. 7, pp. 407, 408, 1862. 

 (Type, Squalus tuherculatus Schneider, orthotypic.) 



Body elongate, moderate, shorter than tail. Head moderate or 

 short. Snout short, obtuse. Eyes small, lower lid without fold. 

 Mouth transverse, with labial folds around angles and with or with- 

 out continuous fold across chin below symphysis. Teeth small, 

 compressed, median cusp triangular with or without smaller lateral 

 cusps at base, 3 or more series in function. Nostrils inferior, near 

 snout end, with nasoral grooves; front nasal valves reach mouth, 

 widely separated by median preoral attachment, each valve w^ith 

 long pointed cirrus; hind valves forming fold at outer side of nos- 

 tril, continued in fold on outer edge of nasoral groove with short, 

 free extremity. Gill openings narrow, last two wider and close to- 

 gether, last three above pectoral. Spiracle small, below eye, poste- 

 riorly very distinct, without or with ridge on hind edge. Fins 

 medium to small. Dorsals two, first behind front of ventral. Anal 

 far behind second dorsal, close to caudal. Anal and subcaudal 

 narrow. 



Indo-Pacific. Fossils known from Miocene deposits. The egg 

 capsules are black and oval and are attached to seaweeds by two 

 fibrous extensions alons: dorsal edsre and at some distance from ends. 



