40 4 



MANUAL OF ZOOLOGY 



of the young are known, the most familiar being that of the 

 male stickleback, which constructs a nest of weeds fastened 

 together by a glutinous secretion of the kidneys, and 

 jealously guards the developing young. In the sea-horse 

 {Hippocampus, Fig. 243) and the pipe fish (Syngnathus) 

 the young are developed in a pouch in the abdomen of the 

 male. In Aspredo, one of the cat-fish tribe, the eggs are 



Fig. 243. — Hippocampus (sea-horse). In P., the operculum is removed to show the 

 gills, br. «/, branchial aperture; brd. p, brood-pouch; d.f, dorsal fin; g. gills; 

 pct.f, pectoral fin. (From Claus and Glinther.) 



pressed into the soft spongy skin of the belly, and thus 

 carried about by the parent. The ova, although containing 

 a large proportional amount of yolk, are always small as 

 compared with those of Elasmobranchs, never exceeding 

 5 to 10 mm. in diameter, and being usually much smaller. 



