276 THE BUTTERFLY VIVARIUM. 



common in the north of France and Germany — that 

 their introduction is still practicable ; but then the 

 experiment must be tried on a large scale, and the 

 Chrysalides must be allowed to expand naturally in 

 the open air ; or, what is better, the insect should 

 be introduced in the egg state; the eggs being 

 allowed to hatch naturally in the open air, and the 

 Caterpillar left at perfect liberty. 



I recollect, when in Paris, seeing at the house 

 of Dr. Boisduval, the well-known entomologist, the 

 Caterpillar of an exotic Butterfly, the magnificent 

 Jason, feeding on the leaves of an orange-tree in 

 his salon. And I believe they were successfully 

 reared ; but whether any attempt was made to 

 naturalize the species in the neighbourhood of Paris 

 by that means I am not aware. 



However, of this I am certain, from the result 

 of a practical experiment about to be described, 

 that if eggs of almost any kind of exotic Butter- 

 fly or Moth were imported and placed in a per- 

 manently suitable temperature, either in the ample 

 area of a large conservatory, or the more limited 

 space of such a Vivarium as the one described in 

 this little volume, that a highly satisfactory result 

 would, with due care, be almost inevitable. We find, 

 in fact, that without care, and simply from increased 



