TELEOSTKI. 



1(17 



fibres of the other without forming a chiasina. The gills are usually 

 comb-shaped, and, as in the Ganoids, lie freely in a branchial cavity 

 under a branchial opercukuu, to which is added a a branchiostegal 

 membrane, supported by branchiostegal rays. The skeleton is char- 

 acterised by the well separated, usually bony vertebra?, and by the 

 b}ny skull, beneath which remains of the primitive cartilaginous 

 cranium often persist. The skin is only rarely naked or apparently 

 \\ithout scales. In such cases the scales are very small and do not 

 project from the surface ; more frequently bony plates and scutes 

 are present in it, especially behind the head. As a rule the skin is 

 covered by cycloid or ctenoid scales which overlap one another. 



The urinary and genital organs open 

 behind the anus either separately or by a 

 common aperture on a urogeiiital papilla. 

 [The kidney is dilated in front to form 

 a head- kidney, which, however, is in the 

 adult, sometimes if not always, largely 

 composed of a tissue resembling lymphatic 

 tissue (Balfour). The generative ducts are 

 continuous with the investments of the 

 generative glands in both sexes, and in the 

 male there is no connection between the 

 testis and the kidney.] 



Only a few Teleosteans ai-e viviparous ; 

 they almost all lay small eggs in enormous 

 numbers in protected places. 



Sub-order 1. Lophobranchii. Teleo- 

 steaiis with armoured skin, elongated 

 tubular snout which is without teeth. 

 The gills are in the form of tufts and 

 the gill slits are very narrow. 



Br 



FIG. 609. Male of Hippocampus 

 with the brood-poucli (Brt). 



Fain. Pegasidae. The body is flattened : pectoral fins large, spread out like 

 wings; pelvic tins small. Fi'i/uxus roJrt/t x L., Kas I Indies. 



Fam. Syngnathidae. The body is cylindrical or laterally compressed. The 

 gill openings narrow, and pectoral tins small ; males with brood-pouches 

 (fig. 609). tii/nf/natJiHx tii-itx L., Pipe-fish : Hippocampux iintiyuiirinii Leach., 

 Sru-lmi>r. Mediterranean. 



Sub-order 2. Plectognathi. Globular or laterally compressed 

 Teleosteans, with immovably fused maxilla and praemaxilla, and 

 narrow mouth. The dermal armour is strong and often bears spines. 

 There are usually no pelvic fins. The gills are comb-shaped. 



