The Bulletin. 33 



The Larva. — The larva of the Tobacco Flea Beetle is about Vg of an 

 inch long when full grown, very slender and white in color, except 

 the head, which is yellowish. (Fig. 19.) 



Fig. 19.— Larva of Tobacco Flea Beetle, side view, enlarged. 

 {Author's illustration.) 



The Pupa. — According to Chittenden, this stage is also white like 

 the larvae. 



Life-history. — The life-history of this insect has never been en- 

 tirely worked out. Most of what follows has been adapted from the 

 writings of Dr. Chittenden. 



The eggs are evidently laid near the food plant, and they hatch in 

 not less than six days. The larvae on hatching, bore into the ground, 

 where they feed upon the roots of the food plant. It seems to require 

 a little more than two weeks for the larvae to become full grown, when 

 they change to pupae beneath the ground. The pupae stage lasts about 

 six days, when the adults emerge and commence feeding upon the 

 leaves. Adults evidently over-winter, according to our experience, 

 as they are found in the tobacco seedbeds as early as the first of April. 

 From that time on they are to be found in or about the tobacco field 

 until the middle of November. From the standpoint of the tobacco 

 farmer, there are three important waves of abundance which, perhaps, 

 correspond roughly to generations of this insect. The first of these 

 occurs about the time tobacco is being transplanted, say from the 1st 

 to the 15th of May; the second about the last of June, and the 

 third the early part of August. This would indicate about three 

 generations, with the length of the life cycle as somewhat longer 

 than a month, which is nearly the conclusion reached by Chittenden 

 from indoor experiments. 



Habits. — The larvae feed beneath the ground on the roots of the 

 host plant. Just how much damage they do in this way has never 

 been determined, though the same insect working on potatoes in the 

 Northern States has been recorded as doing a great deal of damage 

 by injuring the tubers. The adult is very active and seems to prefer 

 working in the late evenings and early mornings. During the heat 

 of the day they are usually to be found hidden away beneath lumps 

 of earth, sticks or stones, or in the shade on the underside of the leaf. 

 Long continued, damp, cloudy weather seems to be a decided natural 

 check upon this insect. It is evidently fatal to the larvae and pupa? 

 which live below the surface and are probably drowned by long con- 



