TRANSPORTATION OF SPAWN AND FISHES. 131 



tive failure of the early attempts to transport the 

 spawn of salmon and trout to Australia has shown 

 that at least the period of suspension can not be in- 

 definitely prolonged. We have found that even a 

 few hours' freezing is decidedly injurious if not 

 fatal to the embryo. The eggs may hatch, but 

 the young most frequently will be found weak 

 and puny, and will rarely survive until the ab- 

 sorption of the sac is completed. To prevent 

 freezing is one of the important points in spawn 

 transportation. Sudden changes of temperature 

 must be provided against. The season during 

 which the spawn are shipped is, in our latitude, 

 the coldest in the year, and a change of temper- 

 ature of 10, much less than the difference "between 

 a warm railroad car and the external air, would 

 be fatal. Moisture we have found absolutely es- 

 sential, the accounts we have heard of dried 

 spawn in the Canton markets notwithstanding ; 

 one hour in a dry, warm atmosphere being suffi- 

 cient to destroy the vitality. Any one who has 

 subjected spawn to microscopic examination will 

 remember how quickly the embryo will cease to 

 live unless the egg be kept constantly moist. 



It is rarely possible, even if the greatest care be 

 exercised, that the spawn can survive even a jour- 

 ney of twenty miles, until ten days after impreg- 

 nation, and unless some special reason exists to 



