94 



At Port Erin, Eledone frequently appears to make 

 unsuccessful attempts to spawn, and in the late summer 

 the body swells up greatly and then begins to degenerate, 

 causing death. Possibly this may be due to the absence 

 of males. 



The largre ova of E. cirrosa are oval, and slightlv 

 narrower at the tip than at the base, measuring about 

 19 x 6*5 mm. A large amount of yolk is present, in 

 tine granules. The only egg envelope, or chorion, is 

 transparent and horny, being drawn out into the attaching 

 string anteriorly. At this end also it is pierced by the 

 tine micropyle. The ovum is surrounded by a clear fluid, 

 and the formative protoplasm is aggregated at the anterior 

 end, and round the circumference of the egg cell. No 

 vitelline membrane is present, the follicular epithelium 

 in the ovary secreting the chorion. 



During fertilisation it is probable that the male, as 

 in Octopus, deposits the spermatophores by means of the 

 hectocotylised arm, in the anterior end of the oviducts. 

 When these spermatophores burst, the free spermatozoa 

 enter the eggs by means of the micropyle. As Eledone 

 lias no nidamental glands, the egg is not covered by any 

 capsule such as occurs in the case of Sepia, or jelly mass 

 as in the egg of Loligo. Since in E. cirrosa the egg is 

 even larger and more yolk-laden than in Sepia, possibly 

 the development may be along similar line-*. 



No account of the development of E. <irros<i can be 

 given, as no living material was obtained, nor has the 

 development of any member of the genus Eledone yet been 

 followed out. Drawings of two embryonic stages of 

 E. aldrovandi are shown on Plate I. Figure 3 is that of 

 a rather younger embryo than is fig. 4 (after Korschelt), 

 and is drawn from some half-developed embryos kindly 

 given by Mr. E. S. Russell, of Glasgow University. 



