PROCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 721 



(c) Some infest the seeds in the fields and are brought into the 

 store with the harvested seeds but do not breed in the store. 



In order to deal with the pulse beetles therefore it is not enough 

 if the seeds are kept in receptacles into which the insects' cannot have 

 access ; but it is necessary to treat the seeds before storage in such a 

 way that they may be fi-eed from the insects which may be present in 

 them due to infestation in the field. 



Below are given the life-history and habits of the common ones 

 occurring in the neighbourhood of Pusa. The names attached to each 

 species are given with reserve, as the identifications require to be 

 corroborated. 



Bruchus chinensis (Plate 107, fig. 1). 



This is the most common pulse beetle hi store. It is found principally 

 in the Store, although in some places it has been observed to infest 

 green pods in the field as well. But its activity in the field is small. 

 In the store, however, it causes serious damage and is capable of breeding 

 ia almost all kinds of pulses. The following three pulse seeds have so 

 far been found to be immune from its attack, viz., the small field-pea 

 {Pismn arvense) and two varieties of Urid {Phaseolus ? radiatus), known 

 in the neighbourhood of Pusa as Aghania and Mungia urid. 



The oval, convex and whitish eggs, looking like small whitish spots 

 on pulse seeds, must have been observed by all. The grubs on hatching 

 from the eggs gnaw into the seeds and the adult beetles emerge through 

 a hole by pushing open a round piece like a lid. Fresh generations 

 occur in the course of about three weeks and, as each beetle lays several 

 hundred eggs, an enormous amount of damage is caused in the course 

 of a short time. Generation after generation occurs in the seeds until 

 there is hardly anything left of the seeds. Taking lots of 25 seeds which 

 were exposed to these beetles, on the average, 7 beetles have been bred 

 out of each large pea seed, 6 from each gram seed, 5 from each khesari 

 (Lafhyriis sativus) seed, 6 from each arliar {Cajanus indicus) seed. These 

 facts demonstrate its injurious capacity very well. 



Bruchus affinis (Plate 107, fig. 2). 

 This beetle attacks peas of all sorts, but the small field pea {Pisum 

 arvense) more than the other varieties. Eggs are deposited on the 

 surface of the green pods in the fields ia January and February. They 

 are elongated oval and cylindrical in shape, measuring 0-66 mm. ia 

 length and 0'25 mm. across and are orange yellow in colour. They are 

 held in position by a clear gummy saibstance exuded with the egg from 

 the ovipositor, this substance covering the egg and Spreading to a small 



