miller] the tobacco WORM 115 



that of celetis blue-black. The obliques on the sides of the cater- 

 pillars differ also. Those on celeus are yellow and supplemented 

 by horizontal lines, which form a triangular figure on each 

 abdominal segment ; those on Carolina are white edged with black, 

 and there are no horizontal lines on this insect. 



When resting, both species assume a sphinx-like attitude, 

 but if annoyed or angered they throw the front portion of their 

 bodies from side to side and spit out a green liquid, which is 

 not poison but undigested food. The ''horn" of the caterpillar 

 being soft and without an opening, has neither the power to 

 sting nor eject poison, newspaper stories to the contrary. The 

 larva is perfectly harmless aside, from the damage which it does 

 to vegetation. 



We find that when the plans of Dame Nature are left un- 

 disturbed by man they are so adjusted that each organism fills 

 the place allotted to it. and with such nicety that no one form of 

 life will, either from lack or over-supply, throw the great whole 

 out of balance. On every plant and animal live other organisms 

 which tend to control the growth and development of their host. 

 Among the natural enemies of the Tobacco-worm and its race 

 are the little Braconids, tiny winged creatures that deposit their 

 eggs under the skin of a caterpillar. Here the eggs hatch into 

 maggots and feed upon the tissues until they no longer require 

 nourishment. 



When fully grown these parasites come to the surface and 

 each, standing upon its caudal extremity, begins to weave a fairy 

 structure of pure white silk, the cocoon in which it is to await 

 the development of its small wings. 



The rapidity with which these wee creatures emerge and 

 envelop themselves in their cocoons is surprising. I have fed an 

 apparently healthy caterpillar and in two hours found it literally 

 covered with these Braconid cradles, that by many are errone- 

 ously believed to be the eggs of the insect. 



It is not wise to kill such a ''worm," for the parasites will 

 be ready to fly from their cocoons in about three days, and if 

 allowed to do so many another big caterpillar will be obliged to 

 serve as "bed and board" for their descendants, while the larva 

 that nourished them, already exhausted by their feeding, soon 

 perishes. 



Where the Braconids are not sufficiently numerous to keep 

 down the Tobacco-worms, Dr. Howard, the government entomol- 

 ogist, advises the destruction of solanaceoiis weeds — natural 

 food-plants — from the margins of fields where tobacco is grown, 



