ORGANS OF EEPEODUCTION. 161 



in the sac, and probably for the attachment of the embryo. 



Pig. 72. — Abdomen of Aspredo hatracfms, with the ova attached ; at a, the ova 

 are remoyed, to show the spongy structure of the skin, and the processes 

 filling the interspaces hetween the ova. (Natural size.) 



The inner walls of the sac are Uned with long filaments, 



M 



