GENUS RAJA. 41 



the ramose vessels of the extremity of the tail; these, per- 

 haps, serve to eject a portion of the air v/hich may be ad- 

 mitted by the branchia in this larger cavity, so as to enable 

 the animal to preserve a proper equilibrium with the water. 



Observation, The connection of these tubes with the 

 cavity of the peritoneum was ascertained by- injecting 

 blue coloured water. 



Fig. 5. Position of the heart and branchia on the oppo- 

 site side of the nucleus, c, heart, d. branchia. b, artery. 

 c. intestine, e, vermiform organ and branch of the artery. 



Fig. 7. Retracted jaw. a, artery, b. intestinal tube. 

 c, c, nerves, e, capitate threads, d, interior palpi. 



Fig. 8. Eye. 



Fig. 6. Jaw exserted, front view with lateral and cen- 

 tral teeth, c, lip. 



Fig. 10. Two pairs of muscles of the dorsal fin. 



Desmption of three New Species of the Genus Raja. By 

 C. A, Le Sueur. Read July Isty 1817. 



Generic Characters* 

 Body flat; pectoral fins large, extending from the head 

 to the anus; branchial apertures 5, placed beneath the 

 body; nose at tip,* distinct from the face. 



SPECIES. 



1. i?. Madura. Head very broad, snout short, en- 

 tire, very obtuse; confounded with the pectoral fin ; tail 



* 1 have called this part, tip of the nose, from Its analagous situation with 

 that part of the human face; for the same reason the part caiied snout may be 

 called the middle of the nose, it is more or less elong^ated, compressed, or de- 

 pressed, and joined to the lip by the septa. 



