24 



I was led to try and breed it to the perfect state, with a view to ascer- 

 taining what species it was the larva of. By digging about the roots 

 of wheat plants I obtained about a dozen specimens, which were 

 placed with a few wheat plants in a large flower pot where they were 

 kept supplied with food by planting occasionally a small quantity of 

 wheat. With the first cold weather they ceased to eat, and were then 

 placed in a sheltered situation until the return of warm weather in 

 the spring, when they were restored to the breeding cage. They soon 

 gave evidence of being alive, and possessing unimpaired appetites ; 

 their rapid consumption of the wheat plants rendered it necessary to 

 renew the supply quite as often as before. They were fed in this way 

 until the month of July, when my absence from home caused them to 

 be neglected ; on my return there was not a vestige of food left. 

 Thinking that the worms had probably died of starvation, I paid no 

 further attention to them until the 26th of August, when on remov- 

 ing a part of the earth from the pot a pupa was disclosed, and on the 

 third of September the first imago appeared, which proved to be a 

 specimen of Agnotes mancus, say. As only two more specimens came 

 out flaring the remainder of September, I turned the earth out of the 

 pot and carefully examined it ; the inspection revealed some seven of 

 the imago in the little cells in which they had transformed, and one 

 larv;c. 



"Among the larvae collected I had noticed one less than half the 

 size of the others, and evidently much younger, which would account 

 for the one still in the larval state. It had attained, however, a size 

 fully equal to that of the others when first brought in during the pre- 

 vious autumn, and hence 1 have formed the opinion that the larva* 

 state does not last longer than three } r ears. This opinion has since 

 been strengthened by the observation of a large number of larval, 

 which appeared readily separable into two sizes, corresponding to 

 those originally collected for breeding. Westwood, in his ' Modern 

 Classification of Insects,' states respecting the larva of an allied species 

 (A. ob8Curu8), which in Europe feeds upon the roots of wheat, rye, oats, 

 barley and grass, that, according to Bjerkander, a Swedish naturalist, 

 ' it is five years arriving at the perfect state.' 



"Curtis, in his 'Farm Insects' (page 161), makes a similar state- 

 ment upon the same authority, and adds that those which he had 

 himself been feeding for ten or twelve months scarcely increased in size 

 during the time. As already stated, however, I am of the opinion 

 that our species are by no means so long lived, but that it attains ma- 

 turity in three years — a period quite long enough, the agriculturalist 

 must think, in which to inflict damage upon the crops." 



As will be seen from this extract, Mr. Pettit is of the opinion that 

 they are three years in arriving at the perfect state. 



The name obtained renders it evident that the species which reside 

 in the ground enter the pupa state in the latitude of northern Illi- 

 nois, perhaps, as a general rule, in July or the beginning of August. 

 Bjerkander states that the worms which he reared entered the pupa 

 state in July. Mr. Curtis says that when the worm arrives at maturity it 

 descends to a considerable depth in the earth, forms an oval cell there. 

 of the particles of soil, and becomes a pupa about the last of July or 

 the beginning of August. Dr. Fitch, as I infer from his article, found 

 several pupse on the 26th of July, and Mr. Pettit discovered a pupa in 



