IN-DOOR APPARATUS. 91 



there will be no danger AYhatever in moving 

 tliem. 



So much, therefore, for the out-door ap- 

 paratus, which, by the way, should not be too 

 far from the dwelling-house, or it will be 

 neglected. It will work w^ell if properly 

 managed, and operations are required on 

 a large scale ; but for ordinary experiment 

 I far prefer the in-door apparatus; because 

 this can be fixed up in a green-house, or 

 other convenient place, and can be watched 

 with greater ease wdthout exposure of the 

 observer to the cold during the winter 

 months, during which the process of hatch- 

 ing will be going on. 



Xow the in-door apparatus consists of a 

 series of boxes, about the size of mignonette 

 boxes, or even smaller ; those used by Mr. 



