DEVELOPMENT OF EEL 



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the same way as the Surinam toad bears her progeny on her back ; 

 while in Solenostoma a pouch for the eggs is formed by the ventral fins 

 and skin. At least a dozen kinds of fishes make nests, of which the 

 most familiar illustration is that of the male stickleback, who twines 



Fig. 360. — Development of eel. — After Schmidt. 

 Change from Leptocephalus shape (L-VI.) to " Elver " shape (VIL). 



grass stems and water-weeds together, glueing them by mucus threads 

 exuded as semi-pathological products from the kidneys, which are 

 compressed by the enlarged male organs. 



Fishes have a less definite limit of growth than most other Verte- 



