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some time doubted whether the eggs found ou bean pods were really 

 those of this species. It has been currently stated that the eggs are 

 laid on the bean pods something as in the case of the Pea Weevil, and 

 it is true that eggs are found upon bean pods fastened very much as 

 those of Bruclius pisi are fastened to pea pods j but upon carefully com- 

 paring them with those laid upon stored beans we find that the two 

 do not fully agree, the former, in color and form, more nearly resem- 

 bling those of B. pisi. We were thus forced to the conclusion that there 

 was some other species working upon beans in the field, as we know 

 there are other species working upon stored beans. Thus we received in 

 January, 1885, Bruchus quadrimaciilatus Fabr., swarming in what are 

 called ^'black-eyed table beans" from Texas that were exhibited at the 

 Atlanta Cotton Exposition. In oviposition in the stored beans this 

 species differs from the common Bean Weevil under discussion in that 

 it deposits its eggs in the beans. We have also received an allied 

 species, Bruchus scutellariSy in 1885 from Mr. F. M. Webster, breeding 

 in beans from the New Orleans Exposition. It is more than probable, 

 therefore, that the eggs which are attached externally to the pods of 

 beans in the field belong to one or the other of these last-mentioned 

 weevils, and in fact they correspond in form and color with those of 

 B. quadrimaculatus. Eealizing that more careful observations were 

 needed as to the habits of the common Bean Weevil in the field, 

 and having a number of different kinds of dwarf beans growing in 

 our garden at " Sunbury" the present summer, we have made a point 

 of looking more carefully into the matter, and our examination showed 

 that the parent Bruchus ohtectus invariably oviposits within the pod, 

 either using her jaws to make a slit or hole in the pod through which 

 to insert the eggs, or waiting until the beans are sufficiently ripe to 

 cause a partial opening of the pod, and then thrusting the eggs into 

 the slit in masses. The perforation is almost always made along the 

 ventral suture near a funiculus, and the eggs are most abundantly found 

 mthin the pods that have already turned yellow and which contain the 

 fully developed beans. Another peculiarity is that the post-embryonic 

 larva, while capable of eating its way into the bean, very much prefers 

 to enter through some i)erforation already made by one of its asso- 

 ciates, so that in the same bean several larvae are frequently found 

 with but one perforation, all having entered through the same hole. 

 That the eggs are frequently thrust into the green pod, though we 

 have not yet found them in such, is proved by the fact that green pods 

 which have been isolated have given out a number of beetles whenever 

 the beans have been fully developed within them, though the pods 

 themselves show no perforation. This would indicate that in the green 

 pods the punctures close up. The development is very rapid, and at 

 Washington beans taken from the field give out the mature weevils 

 from the second week of August on, and commence at once to propa- 



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