FISH IN GENERAL. 95 



shells, as well as those who bring forth living young, are pro- 

 vided with organs of generation resembling the same parts 

 in reptiles. But other fishes., even such as are viviparous, 

 which require fecundation before they can lay, possess these 

 organs in extremely simple forms; that is, in the female, they 

 consist of two membranous bags, the sides of which having 

 various folds, contain the roes within their density until they 

 have acquired the necessaiy development, and escape by 

 bursting the membranous coat which held them ; and in the 

 male, who is likewise furnished with two bags, they contain a 

 great quantity of fecundating liquid, secreted through the 

 glandulous tissue of their sides : these two kinds are what is 

 termed the roe and the milt of fishes. The ovaria of fishes in 

 general, vary in size and in the number of lobes into which they 

 are divided : sometimes one of the two is obliterated or not 

 developed, as is the case in perch ; more commonly they are 

 two, of an oblong form, with the internal side forming several 

 folds, according to the quantity of roes they have to contain. 



Blennies, silures, anableps, and other viviparous species, 

 do not differ from the others in the structure of their ovaries. 

 They form two bags, composed each of two tunics, between 

 which the roes are seated ; in growing, these protrude and 

 hold to the bag merely by a pedicle. In this state their bulk 

 augments, and the germ is developed, as for ordinary fishes 

 it would develope in the water ; both the bags or ovaries are 

 usually connected by a common canal, opening behind the 

 vent, and in front of the urinary orifice. The arrangement of 

 the testiculi or milt is the same ; frequently this issue is not 

 simple, but shaped with a small tongue in both sexes, and 

 it is possible they serve in coition, for this formation is 

 more particularly observed in the genera which have many 

 viviparous species, such as blennies, gudgeons, &c. In eels, 

 lampreys, and others, the ovaries are exteriorly divided 

 into a number of lobes variously shaped, holding the roes, not 



