P1USTIDJE. M7 



1. Genus PRISTIS, Latham. 



Body elongated and depressed. Gill-openings inferior and of 

 moderate width. Spiracle wide and posterior to the eye, which 

 latter has no nictitating membrane. Nostrils inferior. Teeth 

 minute and obtuse. Dorsal fins spineless, the first opposite or 

 nearly opposite the ventrals ; front edge of pectoral free. 



Synopsis of Indian Species, 



A. Caudal fin with a distinct lower lobe. 

 From 23 to 35 pairs of teeth on the snout; in the 



younp their hinder edge is barbed. Dorsal 



fin arises behind the root of the ventral . . 1. P. cuspidatus, p. 37. 



B. Caudal fin without any distinct lower lobe. 

 Prom 17 to 20 pairs of teeth on the rostrum, 



commencing at its base. Dorsal fin almost 



entirely in advance of ventrals 2. P. perrotteti, p. 38. 



From 25 to 32 pairs of teeth on the rostrum, 



commencing near its base. Dorsal fin almost 



entirely posterior to the ventrals 3. P. zysron, p. 38. 



From 24 "to 27 pairs of teeth on the rostrum. 



Dorsal fin opposite ventral 4. P. pectinatus, p. 39. 



38. (l.) Pristis cuspidatus. (Fig. 15.) 



Pristis cuspidatus, Latham, Tr. L. S. 1794, ii, p. 279, pi. 2H, fig. 3 

 (rostrum) ; Day, Fish. India, p. 728, pi. cxci, fig. 3 (see synon.). 



Yahla, Tel. ; Vela meen, Tamil. 



Eostrum narrow and of about the same width throughout, 

 armed with from twenty-three to thirty-five pairs of broad teeth, 

 those on one side (generally the right) often exceeding in number 

 those on the other. This dentition is absent in the foetus, while 



Fig. 15. Pristis cus-pidatus. 



in the immature it only exists in the anterior three quarters of 

 the snout, and in the adult a considerable portion of the base is 

 unarmed. Usually the anterior six pairs of teeth are opposite 

 one another, and the posterior teeth in the immature are mostly 

 barbed behind. Mouth transverse, with a membranous valve 

 (fringed in the young) behind the teeth in the upper jaw, and 

 with a deep notch near the symphysis. The pupil is transverse, 

 with a semicircular flap above and another below ; these flaps are 

 easily raised, depressed, or expanded, according to the stimulus of 

 light received, which they can partially or entirely exclude ; lens 

 very soft. Spiracles large, nearly transverse, posterior to the eyes, 



