APPENDIX. 



257 



hands, lie committed Ms fimiy guests to the waters 

 of the Clyde, the first graylings that had ever swam 

 in Scottish waters. This experiment was after- 

 wards supplemented by obtaining a quantity of ova, 

 and hatching them in boxes set in a small stream 

 conveniently connected with a breeding pond, and 

 so into the Clyde. The arrangement of this pond 

 and stream is so simple and convenient for the 

 purpose of carrying out similar experiments, that 

 we give a diagram of it. 



a The river Clyde. 

 b The pond. 



c Outlet from pond into the Clyde. 

 d d Small stream down the side of the hiU. 

 e Branch of same falling into the Clyde. 

 ///'Gates. 



