1 60 ANGLING. 



from their opinions and report the actual facts as 

 proved by Mr. Shaw. 



The experimental researches of this ingenious 

 observer were carried on for a series of years, have 

 now been frequently repeated with the same results, 

 and may be perfectly relied upon, both for their 

 accuracy and conclusiveness. He captured a pair 

 of breeding salmon in the river Nith on the 27th 

 January, by means of a large landing net, and 

 removed them to a small trench previously formed 

 along side the river. In this trench the deposition 

 of the ova and the process of milting were effected 

 by pressure, (as detailed by Mr. Shaw,*) and the 

 impregnated spawn was carefully collected in a 

 large earthen ware basin, and transferred to a 

 streamlet, the feeder of a small pond, twenty-two 

 feet in length by eighteen in breadth, and so pro- 

 tected by pipes and gratings that no other fish 

 could voluntarily enter it either by ascent or de- 

 scent. The temperature of the streamlet at this 

 time was 40, that of the river water 36. On the 

 2Jst March (54 days after the process above al- 

 luded to), the embryo fishes were visible to the 

 naked eye. On the 7th May (101 days), they 

 had " burst their cerements," and were to be found 

 among the shingle, the temperature of the water 

 being at this time 43, of the atmosphere 45.-f- 



* Edinburgh New Phil. Jour, for January 1838. 



f We have already mentioned that exclusion takes place at some- 

 what variable periods, in accordance with the temperature of parti- 

 cular seasons, the range of variation extending from three weeks to 

 a month. 



