104 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



those employed by the captain and crew of our own 

 fisheries steamer in the Irish Sea and elsewhere, for the 

 purpose of obtaining spawn for the Piel hatchery. That 

 is, the contents of the trawl net when emptied on deck 

 are diligently worked over. Ripe female cod and plaice, 

 as the case may he, are selected, and the mature eggs 

 expelled by gentle pressure on the abdomen into a bucket 

 of (dean sea water. Tvipe males are next secured and the 

 milt expelled into the bucket amongst the eggs. The 

 whole contents are then gently stirred and allowed to 

 settle for a time. The unripe eggs fall to the bottom and 

 by carefully pouring off the water into another bucket 

 these are left behind. The floating eggs which come over 

 in the water are then ready to be taken to the hatchery 

 or returned to the sea. It must be remembered, however, 

 that all floating eggs secured in this manner are not 

 necessarily fertilized. TTe have 1 found from actual ex- 

 perience that unfertilized plaice eggs may continue 

 floating and remain fairly transparent for a whole week 

 after being expelled from the fish. 



If all the 40 cod and 12 plaice dealt with were females, 

 then the cod apparently gave 3,000,000 eggs each and the 

 plaice about. 166,000. 



These facts are sufficiently remarkable to those 

 acquainted with the work which has been done on this 

 subject to call for some explanation. The besl estimates 

 of the number of eggs contained in the ovaries of ripe 

 female cod and plaice give from 3 to (>l millions in the 

 case of the cod, and 148,000 to -1ST, 000 in the case of the 

 plaice, the exact number of course varying with Ihe size 

 of ihe fish and the locality where they were raptured. 

 Captain Cappelman, then, obtained by far the greater 

 portion of the ovaries by stripping the fish. Now, if is 

 well known that all the ^gg^ present in the ovary of the 



