86 



" ENDEAVOUR " SCIENTIFIC RESULTS. 



slightly enlarged median series of dorsal tubercles, which, 

 however, may be lost with age. It differs from the only species 

 recorded from Australia, S. australis, Began 1 , in having the 

 dorsal denticles tricarinate, and the greater part of the pectorals 

 and ventrals naked ; the tubercles on the snout are much larger 

 and differently arranged, the interspace between the spiracles is 

 less than the interocular width, and the colour marking is 

 altogether different. 



Loc. Great Australian Bight, Long. 127-128 E., 160-200 

 fathoms ; June, 1913. 



FAMILY AETOBATID^E. 

 Genus AKTORATUS, IHainville. 

 AKTORATUS AUSTRALIS, Macleay. 

 (Fig. 3.) 



Aetobatus australis (Macleay), McCulloch, Zool. Results 

 " Endeavour," i., pt. 1, 1911, p. 15 synonymy. 



Through the kindness of Mr. E. R. Waite, I have been able to 

 compare a New Zealand example of Aetobatus tenuicaudatus, 

 Hector 2 , with others of A. australis from New South Wales. 

 In general form, colour markings, and all other external 

 characters they are identical, but the teeth apparently afford 



Fig. 3 Teeth of Aetobatus tenuicaudatus (left) and A. australis (right.) 



specific characters. Those of the New Zealand species are 

 narrower in a longitudinal direction, and more numerous than in 

 A. australis ; the differences are illustrated in the accompanying 

 figures. 



1 Began Ann. Mag. Nat. Hist. (7), xviii., 1906, p. 438. 



2 Hector Trans. N. Zeal. Inst., ix., 1877, p. 468, pi. x. Id , Waite, 

 Rec. Cantb. Mus., i., pt. 2, 1909, p. 152, pi. xxiii. 



