No. I .] GAR-PIKE AND STURGEON. \ \ 



the same hatching cases (v. U. S. F. C.BulL, 1893, No. xviii, 

 PP- 336-337) as he had used at Delaware City in the hatching 

 of Sturgeon. Fish were freshly captured : the eggs were ex- 

 truded by pressure and received in an earthenware dish. Here 

 they were retained dry and shortly fertilized by a few drops of 

 milt from a ripe male. They were then stirred ; several min- 

 utes later water was added and as the eggs became adhesive 

 they were quickly spread under water over netting-covered ^ 

 hatching-trays. The thick, glairy mass which surrounds the 

 eggs of Acipenser was not noted. Attachment was speedy; 

 and the egg-covered trays, taken out of water, were taken 

 back to Edwardsville — a two hours' row — with no further 

 precaution than that of moistening the trays to guard against 

 the drying of the eggs. This mode of transport the writer 

 notes to emphasize the hardiness of the eggs, since it was 

 later found that the proportion of eggs lost on these trays was 

 scarcely greater than of those which were at once placed and 

 retained in the floating hatching-boxes. 



Artificial fertilization was repeatedly tried and always with 

 favorable results ; for this purpose fishes were transported 

 living from the spawning grounds to Edwardsville. In obtain- 

 ing the eggs it was found most convenient to excise the entire 

 ovaries ; from these the eggs were readily taken, and though 

 not appearing to separate freely from their follicles they 

 proved nevertheless capable of fertilization. The hatching 

 boxes with their enclosed trays were floated near the shore in 

 about five feet of water at the end of the wharf of Mr. Perry. 

 Here the water was muddy and far from pure, but the eggs 

 proved hardy and the loss from fish fungus was usually incon- 

 siderable. On a tray where a loss of about 50/0 of the eggs 

 was recorded, the mortality seemed mainly due to the crowded 

 condition of the eggs. For convenience in securing develop- 

 mental stages a mass of eggs were scraped from the trays and 

 kept in the laboratory in earthen pans until required. As a 

 fixing reagent (alcoholic and aqueous) picro-sulphuric acid was 



1 In his present experiments tiie writer employed "canopy netting" for the 

 hatching frames. This material is of much finer texture than " mosquito netting," 

 and its circular perforations seem more favorable for the attachment of eggs. 



