548 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



abdomen in the same way as the Crayfish, without 

 suffering some loss of the eggs, but the very fact that the 

 cement glands are placed on the under-surface of the 

 abdomen, instead of in their usual position on the 

 pleopods, suggests that a similar process is gone through. 

 Experiments on a female Hermit Crab will show that 

 though glands on the pleopods would not be much use in 

 filling a brood pouch formed by the flexion of the 

 abdomen with secretion, similar organs on the under- 

 surface of the abdomen would be very efficacious for that 

 purpose. Fertilisation in such a chamber would be just 

 as possible in Eupagurus as it is in the Crayfish. The 

 empty spermatophores are almost always to be found 

 adhering to the pleopodal eggs, and they can only have 

 got there during oviposition. It is possible that the 

 extended breeding season of this species is not uncon- 

 nected with a certain wastage of eggs. 



In brief, the process as conceived above would be as 

 follows : — The male deposits the spermatophores on the 

 under-surface of the female (possibly in a space between 

 the columellar muscle and the body into which the 

 oviducts open when the tail is flexed) ; the female flexes 

 her abdomen underneath the thorax, fills the space with 

 mucus, dangles her pleopods into the chamber and pours 

 out the ova. The ova and sperm are mixed in the 

 chamber, as in the Crayfish, and the eggs become attached 

 to the pleopods, also as in that animal. The process 

 of oviposition might possibly be carried on inside the 

 whelk shell without flexing the abdomen. 



Embryonic development The eggs are attached to 



the setae of the pleopods on the second, third and fourth 

 abdominal somites in dense purple clusters.* Up to the 



* The ova of E. prideauxii seem to be red, both ovarian and 

 after extrusion. 



