310 THE ELASMOBRANCH FISHES 



into the cloaeal opening of the female and fixed in position by the erection of 

 terminal pieces. The sperm cells reach the groove or tube in the claspers and 

 are forced thence into the oviduct of the female by a current produced by the 

 siphon (Acanthias). The cells traverse the oviduct to the region of the fal- 

 lopian tube where they remain until the mature eggs enter the oviduct and 

 fertilization takes place. 



