insects, by destroying their larvae, so injurious to 

 the interests of agriculture. All are parasitic, 

 and in habit, they may be compared to the Ich- 

 neumon amongst the quadrupeds, an animal said 

 to break the eggs of the crocodile, and even to 

 penetrate the abdomen of that formidable reptile, 

 in order to devour the living viscera. 



The female, in this interesting genus, w^hen 

 about to deposit her eggs, becomes very active 

 and impatient, flying from leaf to leaf, in search 

 of a proper nidus; having found a caterpillar of 

 suitable magnitude, she places her eggs either 

 upon the skin, or by puncturing it, within the 

 body, notwithstanding the convulsive efforts of 

 prevention made by the victim. I was witness 

 to a somewhat curious fact in relation to one 

 of these insects; observing an object closely 

 resembling a caterpillar, resting on a leaf, I was 

 preparing to take possession of it, when an Ich- 

 neumon alighted on the leaf, and proceeded to 

 examine the object of my attention ; it ran briskly 

 up to it, and touched it first on one side, and 

 then on the other, with its vibratory antennae; 

 but it finally departed without any attempt at 

 oviposition. This deportment excited my suspi- 

 cions in regard to the nature of the supposed 

 caterpillar, and on examining it more closely, I 



PLATE XXII. 



