* American Fisheries Society 93 



uremenl of the et^gs in their later stages, witli the same stan- 

 dard that was employed near the heg'inning of the period 

 of inciil)ation. Tliis condition was, of conrse. somewhat 

 mitigated in those instances where eggs well e\etl were trans- 

 ferred to other stations for hatching and a new standard of 

 measnremenl \\as adopted at the station recei\ing them. 

 Howe^■er, nntil recently the fact of there being an increase 

 has recei\'ed little or no recognition, (»r at least but slight 

 practical application. 



During the last few years various tests and measurements 

 have afforded a definite basis for discarding the old theory. 

 We may, in fact, boldly a(h'ance the statement that probably 

 most fish eggs increase in size, not onl)- during the early 

 absorptive period Init continuousl\' up to the time of hatching. 

 For a numljer of species this fact has jjeen demonstrated. 

 Rainbow trout eggs have shown, in the tests, ]jractica]l\- no 

 increase. But all other species tested have exhibited \arying 

 degrees of growth, in the whitefish reaching 15 ])er cent. 



A resume of the obser\'ations made at a nuiuber of the 

 Bureau's stations will show the ])asis of these conclusions. 



WHITEFISH. 



During the winter of 1906 Superintendent Downing of the 

 government station at Put-in Bay, Ohio, made some \cry 

 interesting observations as to the increase in size of whilefish 

 eggs. A'arious lots were counted from time to time and it 

 was quite conclusively demonstrated that the eggs enlarged 

 in size more than 15 per cent. It was further shown that the 

 rate of increase was (juite unnoticeable at first, 1)ut the older 

 the eggs the more rapidly they grew. In the winter of 1907 

 the use of the von Bayer gauge and chart showed that green 

 whitefish eggs ran 42,000 to the quart, and eyed eggs 36,000 

 to the (|uart, a bulk increase of approximateh' 1-1- per cent. 



Superintendent (jreen, of the Cape A^incent, X. Y., station, 

 noted that whitefish eggs increased 3 per cent in size during 

 the month jusl ])rior to hatching, ddiis seems to corroborate 

 the ol)ser\alions of Mr. Downing that the increase largely 



