54 Memoirs of the Indian Museum. [Vol.. II, 



but unfortunately only the head and tail were preserved. The teeth of the upper jaw 

 measure 28 mm. in transverse diameter, but there is some evidence to show that the 

 mouth is relatively smaller in this species than it is in M. nieiihofii. Judging from 

 the analogy of the few young examples of M. maculata I have examined in detail, 

 the adult specimen (a female) must have measured about 78 cm. across the disk, but 

 in making this statement I take it for granted that there is little difference in propor- 

 tions between the adult and the young of the species. 



I have not seen any specimen of M. maculata with a superciliary horn,^ or of 

 either of the Indian species of the genus with a caudal spine. 



Genus AËtobatis, Müller and Henle. 



This genus is separated from Myliobatis by the character of the teeth. In all the 

 specimens I have seen those of the lower jaw project from the mouth in the form of a 

 plate with parallel sides and an obtusely pointed tip. The nasal flap in these specimens 

 is deeply emarginate. Day says that the tip of the lower tooth-band is sometimes 

 broken off and that the free edge of the nasal flap is then straight as it is in Myliobatis 

 {Fishes of India, ii, p. 743), but it is clear from specimens named by him that he confused 

 Aetohatis guttata with Myliobatis maculata in some cases. 



Great confusion still exists as regards the species oi Aètobatis. Most recent authors, 

 following Günther {Cat. Fishes, viii, p. 492), recognize only one species, namely A. 

 narinari ; but at least two distinct forms occur in Indian seas and it is clear that 

 neither is the same as the American and African species. 



As regards the last point, there is of course no positive proof that there are not 

 two forms (or even more) in the Atlantic Ocean (one or more of which may be rare) 

 as there are in the Bay .of Bengal. But figures pubhshed by Duméril {Arch. Miis., x, 

 pi. 20, Paris, 1861) and by Jordan and Everman {Bull. U. S. Nat. Mus., No. 47, vol. 



iv, pis. 37 and 38, 1900) represent a species which differs in at least two characters 



namely, the shape of the snout and coloration — from any Indian specimen I have seen. 

 Duméril shows, moreover, that the adult of the form he called Aetobatis latirostris, the 

 type specimens of which came from the mouth of the Gaboon, does not differ mate- 

 rially from the young as regards coloration. 



Jordan, who examined specimens from Florida {Guide to the Study of Fishes, vol. 

 i, fig- 349> i9<^5) as well as from the West Indies and Mazatlan {Bull. U. S. Nat. Mus., 

 No. 47, vol. iv, p. 2753) and found no difference between them, decided with Everman 

 that " this species " [i.e., Aetobatis laticeps, Gill] " is probably not different from 

 A . nannari " . 



There is little doubt that Aetobatis laticeps. Gill, is a synonym of A. latirostris, 

 Duméril, whüe Euprasen {Kong. Svens. Vet. Akad. Nya Handl., xi, p. 218, 1790) says 

 regarding the species he described as Raja narinari :— " Habitat in India occidentaH, 

 juxta Insulas Caribaeas, in portu Carénage Insulse St. Bartholemei." The figure 



' In a half-grown specimen taken in a seine-net on the beach at Puri in March there is a distinct 

 but low rounded eminence on either side just in front of the eye. 



