50 



The Endoparasitic Development of the Khizocephala. 



These diagrams (Text fig. 1 3) are constructed from the actual sections drawn on Plate 5. 

 In Figures 10 and 11 (Plate 5) the invagination to form the perisomatic space (pc) has just 



pc 



pc 



6c 



Text fig. 12. 



r 



,1/m. 



<V \frc 



** 6p r <? 



Text fig. 13. 

 v/n = visceral mass, be = mantle cavity, pc = perisomatic cavity, op = opening of perisomatic cavity. 



begun. It always begins in the same place namely between the visceral mass of the Saccu- 

 lina and the intestine of the crab, and at the posterior part of the central tumour. The cells 



