120 MALACOP. ABDOM. SALMON FAMILY. 



different rivers. The running commences in some 

 streams much earlier than in others, a circumstance 

 thought to depend on the temperature. The north- 

 ern rivers are observed to be earliest. The females 

 make their appearance first ; and the Grilse, or 

 young fish on their first return from the sea, gene- 

 rally precede the more mature individuals. 



The ova continue under the gravel before they 

 are hatched a longer or shorter period according to 

 circumstances, in general from a hundred to a hun- 

 dred and forty days. Shortly after being excluded, 

 the fry work their way upwards through the gravel. 

 At this early age they are translucent and shapeless^ 

 the head small and rounded, and all the fins conti- 

 nous, forming a loose membrane round the body. 

 In a short time they assume the general aspect of a 

 fish; the fins becoming separated; the colours gradu- 

 ally deepen, and when they reach about two inches 

 in length, they are marked on the sides with conspi- 

 cuous transverse dusky bars, and the tail fin becomes 

 deeply notched. The first migration to the sea takes 

 place from the beginning of March to the end of May^ 

 in the second season after birth. The fry are then 

 called Smelts or Samlets, and in some places, Lasp- 

 rings. On reaching the mouth of the river, they re- 

 main for a time where the water becomes brackish by 

 the mixture of salt water, and thus prepared for the 

 change they launch out into the sea. The salt water 

 is either favourable to their growth from its very 

 constitution, or because it affords them most nutri- 

 tious food, for they rapidly increase in size and 



