.590 



ANATOMY OF VERTEBRATES. 



Fishes the spermatozoa resemble those of the Perch, fig. 400 : but 

 in some, e. g. the Loach, there is a small swelling at the insertion 

 of the appendage, as in fig. 401. In a few the ' body ' is scarcely- 

 indicated, e. g. in the river Lamprey, fig. 402 : in the Petromyzon 

 marinus the body expands into an egg-shape. 



400 401 -102 



Sliemixitozoa of Pcrca 

 JlavlatiUs. CC(T\'X. 



Spermatozoa of Coxitis 

 fossilU. cccvi. 



Spermatozoon of Petvfinnjzon 

 fliiviattlvi. CCCT'I. 



The spermatozoa in the Plagiostomes are very long, with an 

 anterior cylindrical body. This is proportionally shortest in 

 ChimcBru monstvosa, and is disposed in three spiral coils : in 

 Scyllium canicula it is about half the length of the spermatozoon. 



403 



404 



405 



A. Siiermatuzoa of 



B. .Spermatozoon of 

 Ttjrpcdo Narce. cccn'l. 



Spermatozoa within tbe 



sperm-cell {.Torpedo Narc£). 



CCCVI. 



is straight, and tapers at botli ends: in Sci/m)H(s nicaensis, fig. 

 403, it is spirally disposed. In Spinax acaiitliias, the Rays and 

 Torpedos, fig. 404, tlic spiral coils are rather closer, usually four 

 in number: in Haia oxijrhi/nchus the coils are more numerous, 

 but only afi^ect the anterior half of the body. 



In the Plagiostomes tlie spermatoa appear as one or more nuclei 

 witliin tlie sperm-cell, like those in fig. 399, h : but they are not, 

 as in Osseous Fishes, excluded in that state. ' In each spermatoon 



' cocvi. vol. iv. p. 484. 



