CHONDEOPTERYGII. SELACHOIDEI. 



opposite the interspace between the pectoral and ventral ; caudal 

 with a distinct lower lobe. 



Eespecting the colours in these fishes, I have observed that 

 black spots or marks on the fins frequently become fainter in 

 examples which have been preserved some time in spirit, more 

 especially if they have been removed from the alcohol and per- 

 mitted to dry. 



The fishes constituting this large and widely distributed genus 

 have been subdivided by some authors into several genera, by 

 others into the like number of subgenera or divisions, which latter 

 is the course that I have adopted. 



Synopsis of Indian Species. 



A. Teeth with smooth edges; all oblique 

 and without swollen bases. (Scoliodon.) 

 Pectoral fin not reaching to below dorsal ; 



length of base of anal nearly equalling 

 its distance from the ventral ; second 



dorsal posterior to base of anal. Groove 



at angle of mouth not extending on to 



the upper jaw 1. C. laticaudus, p. 9. 



Pectoral fin reaching to below origin of 



dorsal ; length of base of anal nearly 



equalling half its distance from the 



ventral ; second dorsal over end of base 



of anal. Groove at angle of mouth not 



extending on to the upper jaw 2. C. acutus, p. 10. 



A well-marked groove at the angle of the 



mouth extending a short distance along 



both jaws 3. C. walbeehmi, p. 10. 



B. Teeth with smooth ed^es ; those in the 



centre of the lower jaw smaller than 

 those at the side, the latter swollen at 

 their bases and having an oblique and 

 narrow cusp. Upper teeth flat and 

 oblique. (Physodon.} 

 Snout elongated ; end of base of first 

 dorsal above origin of ventral ; second 

 dorsal small and' posterior to the base 

 of anal 4. C. miillcri, p. 1 1 . 



C. Teeth with smooth edges ; all narrow and 



standing on a broad base, the upper 

 erect or slightly oblique; the lower 

 erect. (Aprionodon.) 

 Second dorsal as large as the anal and nearly 

 equal in size to the first dorsal. Nostril 

 with a distinct valve inferiorly. Teeth 



5. C. ncutidem, p. 11. 



D. Teeth with smooth edges, except the 

 bases of the upper ones, which are 

 serrated. (Hypoprion.) 

 Snout pointed. The bases' of the teeth in 

 the upper jaw serrated on both sides . . 6. C. madoti, p. 12. 



