FISH EGGS 



317 



catch these products on extrusion in a jar containing 

 a little sea water. It is no use trying to fertilize eggs 

 unless naturally extruded by the female ; but, in the 

 cae-e of males, milt approaching ripeness and obtained 

 by dissection is sometimes sufficient for the purpose. 



If a ripe female is obtainable but no male can be 

 found, the eggs should be allowed to remain in sea 

 water for some hours after extrusion before being 



FIG. 205. HORNY EGG CAPSULE OF (a CHIMERA, (6) SCYLLIUM. 



FIG. 206. DEMERSAL OVA OF A SHORE FISH (GOBIUS MINUTUS) 

 IN AN EMPTY SHELL. 



examined, so as to allow them to attain as far as 

 possible their normal size after distension on contact 

 with water. 



Pplagic eggs, if not obtained direct from the parent 

 and artificially fertilized, may very often be found 

 among the gatherings of tow nets. When obtained, 

 they may be kept alive for a long period, and their 

 development and hatching watched if they are kept 



