70 NATUEAL HISTOEY OF THE SALMON. 



Ibs. weight, was caught, in excellent spawning 

 condition, and the keeper having provided, from 

 the pond, a number of male parrs, artificially 

 reared, in a similar state, the ova was fecundated 

 by their milt. Two parrs were required for every 

 400 or 500 ova. The milt of the parr appeared 

 to have the same effect on the ova as that from 

 the male salmon, and it was expected, therefore, 

 that they would hatch. They were put in boxes 

 by themselves, and carefully attended. M. Coste, 

 when visiting the ponds, recommended that ex- 

 periments should also be made upon the ova of 

 sea-trout (salmo trutta), impregnated by the milt 

 of salmon (salmo salar); but it was thought, 

 as there were no additional ponds to receive 

 the fry, it would be better not to give occa- 

 sion to any one to say that the fry had been 

 mixed; and this principle has been followed 

 out all along in the Stormontfield experiment, 

 as nothing but the salmo salar has been ex- 

 perimented upon. The keeper, however, fur- 

 nished the writer with a few ova taken from a 

 female sea-trout, impregnated with the milt of 

 a grilse, and, in 60 days, by the syphon process, 

 the water at a temperature of 44, the ova were 

 hatched. They appeared to be weakly, larger 



