PEA AND BEAN WEEVILS. 



BRUCHID/E 



There are, relatively, not many of these beetles and, for 

 the most part, they are less than .25 in. long. They 

 differ from most of the Chrysomelidae by having short, 

 saw-toothed antennas, and the tip of the abdomen is 

 exposed. The larvag live in seeds, especially of Legumes, 

 and are often called "weevils" a term which is confusing 

 because of its application to the Rhynchophora. We 

 have, all of us, eaten hundreds of the larvas with our peas 

 and beans, but what's the difference? The eggs are 

 usually laid upon the pod when the peas, for example, are 

 quite small, and the young larvae bore inside-. 



Spermopliagus has two slender, jointed spurs on each 

 hind tibia. The only Northeastern species, robinia, 

 breeds in the seeds of the locusts (Robinia and Gleditschia) . 

 The adult is about .3 in. long; dull reddish-brown, clothed 

 with grayish-yellow pubescence; elytra with small, black 

 spots arranged in five irregular, transverse rows. 



This is the large and common genus. 

 The hind tibias are without jointed spurs 

 and the prominent, front coxae touch each other. Only 

 two species (Plate LXXXIV) will be mentioned, but 

 many others may be obtained either in ordinary collecting 

 or, better because it gives food habits, by breeding from 

 seeds of wild plants. B. pisorum, the Pea Weevil, has 

 a notch on the middle of each side of the pronotum and a 

 tooth on the outer side of each hind femur. It is black, 

 densely clothed with reddish-brown and whitish hairs; 

 pronotum with a triangular, whitish space in front of 

 scutellum; elytra with yellowish, grayish, and whitish 

 hairs. There is but one generation a year and this species 

 does not breed in dry peas. The adult hibernates. The 

 newly-hatched larva has legs but it loses these when it 

 becomes a fat, sedentary grub. Pupation occurs within 

 the seed. B. obtectus, the Bean Weevil, has no notch on the 

 sides of the pronotum and each hind femur has two fine 

 teeth in addition to a larger one near the tip. It is black, 

 clothed with grayish-yellow pubescence; abdomen dull 

 reddish-brown; antennae black, the apical and four basal 



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