298 



•egg-laying occurs generally at night. Where the insects are abundant 

 -a single pod will often be found to carry as many as 15 or 20 eggs, 

 which is an evidence of faulty instinct, since only one 

 larva can develop in a single pea. The newly hatched 

 larva is deep yellow in color, with a black head, and 

 bores directly through the pod into the nearest pea, 

 the hole in the pod soon growing over, while a mere 

 speck upon the side of the pod is the only indication 

 of its entrance. The statement has been generally 

 ,^ made that, in feeding, the larva seems in the majority 



Fig. 41.— Egg of Pea 5 &' J J 



w^eevii— enlarged (af- of cascs to avoid the germ of the future sprout so that 

 ter Riley). most of the " buggy " pcas will germinate as readily 



as those which have been untouched. This must, however, now be 

 qualified, as we shall show in a later paragraph. The full-grown larva 

 is indicated at Fig. 40c. Before transforming to pupa, it cuts a circular 

 hole quite to the thin outer membrane of the pea, thus providing for 

 the future exit of the beetle. It then lines the interior of its excava- 

 tion with a thin smooth layer of paste, excluding all excrement, and 

 then transforms to the pupa state. The adult beetle in issuing has 

 only to eat through the thin membrane left by the larva. It has been 

 proved that the beetle would die if the larva had not prepared this 

 passage way, and has been asserted that it will perish if the hole is 

 pasted over with a piece of paper thhiner than the hull itself. 



Sometimes many of the beetles will issue in the fall of the year, but 

 as a general rule they remain in the peas through the foUoAving winter, 

 and many are planted with seed peas. As far as is known the insects 

 on issuing will not oviposit upon the dry peas, and a sure remedy will, 

 therefore, be found in keeping seed peas in a close recejitacle over two 

 seasons before planting. The beetles will all issue at the customary 

 time, but will soon die. When it is necessary to plant the first season 

 the entire lot of seed should be thrown into water, when the " buggy" 

 ones will fl(>at, and should be removed and destroyed, sound ones only 

 being planted. Infested peas may also be disinfected by placing them 

 in a tight vessel with one of a number of different insecticides, among 

 which may be mentioned camphor, chloroform, ether, and bisulphide of 

 carbon, the latter being the cheapest and most efficacious. 



We have just noted the current idea that the larva, while working in 

 the interior of the pea, generally avoids the germ or plumule and from 

 this fact the impression has become more or less prevalent that i)eas 

 which have been eaten by weevils are none the less available for seed. 

 There has been many a discussion on this subject in the columns of the 

 agricultural press, and while the weight of evidence has always been 

 contrary to the use of damaged seed peas, still the question can not be 

 said to have been definitely set at rest before the publication of the re- 

 sults of Prof. E. A. Popenoe's careful experiments, in Bulletin No. 19 of 

 the Kansas State Experiment Station. This investigator conducted a 



