270 GnVINOBONTES. 



short, truncate. Vertical fins confluent . No pelvic hone. Air- 

 hladder absent. 



Jaws without median suture 10. OrthagorisciiSy p. 317. 



First Group. TRIODONTINA. 

 1. TRIODON. 



Triodon, (Heinwardt) Cuv, Rhgne Anim. 



The upper jaw divided by a median suture, the lower simple. 

 Body covered with small osseous, scale-like, spiny subimbricate 

 laminae. Two distinct nasal openiijgs on each side. Tail long, ter- 

 minating in a distinct bilobed fin ; Caudal and anal fins short. 

 Abdomen dilatable into a very large, compressed, pendant sac, the 

 lower part of which is merely a flap of skin, into which the air does 

 not penetrate. The sac is kept expanded by the very long pelvic 

 bone. Skeleton ossified, with the ribs well -developed. 



Indian Ocean and archipelago. 



1. Triodon bursarius. 

 Renard, Poiss. Moll. ii. pi. 30. fig. 142 ; Ruysch, Amb. p. 31, pi. 16. 



fig. 1. 

 Triodon bursarius, (Retnw.) Cuv. Rhgne An. ; Bleek. Verh. Bat. Gen. 



xxiv. Blootk. p. 20, and Atl. Ichih. Gymnod. p. 84, pi. 10. fig. 1. 

 macropterus, Less. Voy. Coqu. Zool. pi. 4 ; Dareste, Ann. Sc. 



Nat. xii. p. 68, pi. 1. fig. 1 (osteol.). 



B. 6. D. 10. A. 9. C. 18. 



Eye large, about one-fourth of the length of the head. A large 

 irregidar black spot edged with yeUow on the upper part of the ven- 

 tral sac. 



Indian Ocean and archipelago. 



a-b. Adult (19-21 inches long) : stufifed. Mauritius. Purchased 



of Mr. Cuming. 

 c-d. Adiilt: stuffed. India. 



Second Group. TETRODONTINA. 



Globcrfishes, well known from their being able to fill their body 

 witb air, and to float on the surface of the water belly upwards. 



2. XENOPTERUS. 



Xenopterus, Bibron, Rev. Zool. 1855, p. 281. 



Chonerhinus, Bleek. Atl. Ichth. Gymnod. p. 77 (not before charac- 

 terized). 



Jaws di\-ided by a median suture. Body with small dermal ossi- 

 fications, each with two or three roots and a spine. Dorsal and anal 

 fins many-rayed. Nostrils funnel-shaped, with fringed margin. 



Indian archipelago. 



