SPAWN OF CHITON AND OF THE CEPHALOPODA 



127 



to elevate the posterior part of the girdle, and to poiir out a 

 continuous stream of flaky white matter like a fleecy cloud, 

 which proved to be of a glutinous nature. It then discharged 

 ova, at the rate of one or two every second, for at least fifteen 

 minutes, making a total of 1300 to 1500, each being about 

 YjjQ inch diameter. The ova were shot into the glutinous cloud, 

 which seemed to serve as a sort of nidus to entanjjle the ova and 

 prevent them Ijeing carried away. The subsequent development 

 was rapid, and in se^'en days the young Cliiton was hatched, 

 being then about J^ inch long. Loven has described the same 

 species as laying its eggs, loosely united in clusters of seven to 

 sixteen, upon small stones. There is probably some mistake about 

 the identification, but the ol)servation illustrates the varying 

 methods of oviposition among allied forms. 



Not very much is known with regard to the ovipositing 

 of the Cephalojjoda, especially those which inhalit deep water. 

 Masses of ova arranged in 



Fig. 43. — Egg-capsules of A, Seiria elegans 

 Orb., aud B, OdojJus vulcjaris Lam. 



very various forms have occa- 

 sionally been met with float- 

 ing in the ocean, but it is 

 next to impossible to deter- 

 mine to what species, or even 

 genus, they belong.^ 



In Loligo ^)M7ic^ato the 

 ova are contained in small 

 cylindrical cases measuring 3 

 to 4 in. by }^ in., to the 

 number of about 250 ova in 

 each case. Hundreds of these 



cases are attached together like a l)undle of sausages or young- 

 carrots, and the movements of the embryos within can be dis- 

 tinctly noted. Sepia officinalis lays large black pear-shaped 

 capsules, each of which is tied to some place of attachment by a 

 kind of ril)bon at tlie upper end of the capsule, the whole form- 

 ing a large group like a bunch of grapes. Octo^yus mdgaris 

 deposits thousands of small berry-shaped ova, attached to a string 

 which runs along the centre of the mass (Fig. 43). 



The so-called shell of the female Argonauta is nothing more 



^ E.xaniplcs will be found in Journ. Linn, Soc. Zool. xi. p. 90 ; Ann. Sc. Xat. 

 XX. p. 472 ; Zcit. iciss. Zool. xxiv. p. -119. 



