EXPORTATION OF FISHES AND HATCHING APPARATUS. 091 



that geuiis, which are distributed throughout the fresh-water lakes and 

 streams of the Northern Hemisphere between latitude 40^ and the Arc- 

 tic Circle. The representatives of the genus in Britain are the vandace 

 of Loch Mabin and Lake Windermere, the x>oic an of Loch Lomond, the 

 pollan of the Irish lakes, and the givyniad of certain lakes in Wales. 



In America there are several species, some of which ascend rivers from 

 the sea, while others, of which Coregoims albus is one, are chiefly con- 

 fined to lakes. The American commissioners express the opinion that 

 few fish will better repay efforts for their multiplication than this white- 

 fish, and large sums are being spent in the propagation and introduction 

 of this species to the various northern and winter stations, where they 

 are not found naturally. 



The excellence of the whitefish as an article of food is described by 

 all travelers in the northern regions of America, where it forms the 

 staple diet of the Indians and trappers during a large part of the year. 

 It is a plump-bodied fish, free from small bones, with firm, delicately- 

 flavored flesh in large white flakes. It is highly nutritious, but at the 

 same time free from the rich oil which renders the salmon so cloyiug to 

 the appetite when constantly used as food. 



The size of the full-grown fish is iiretty uniform if caught in the same 

 locality; but in some places they reach a weight of 20 pounds, and 

 even 40 pounds, while in others the average is about 2 pounds weight, 

 the difference being no doubt due to the paucity or abundance of their 

 favorite food, which consists of small crustaceans and shell-fish. They 

 grow rapidly, the weight increasing about f pound for each year's growth, 

 the fish of the first season, or about eighteen months old, generally 

 weighing 1 J pounds. They are very fertile, the number of eggs depos- 

 ited by the female being about 10,000 for every i^ound-weight of fish. 

 They have the great advantage of being in season and procurable at all 

 times of the year, although they have regular migrations from the shal- 

 low to the deeper waters of the lakes, and to the shoals at the outlets of 

 the lakes for the purpose of spawning. This takes place in the month 

 of November, or just before the winter sets in. At this time the tem- 

 perature of the surface water is about 43° in the larger lakes. When 

 owing to the shallowness of the water in which the ova are deposited 

 the temperature falls to 34° to 35<^ during winter, they do not hatch out 

 until April, but the usual period is 100 days between the spawning of 

 the ova and the emergence of the young fish. 



In the case of the ova recently imported, the period seems to have 

 been under 80 days, as they were spawned about the 15th November, 

 and the young fish hatched out in Christchurch on the 3d February, 

 which goes to prove that the low temperature in their native waters only 

 retards the development of the ova, and that it is not essential that they 

 should remain dormant for so lengthened a period. This is a very im- 

 portant question as affecting the propagation of this fish in New Zealand, 

 as, if the continued low temperature of the great lakes of North America 



