FAM. 77. BRUCHIDAE.—_Prosternum extremely short; in front perpendicular; behind the coxae, forming merely a transverse lamina with pointed extremity. Hind femora more or less {277}thickened._ This comparatively small family includes about 700 species of small, unattractive beetles. The larvae live in seeds; hence some of the species are liable to be transported by means of commerce; some of them do considerable injury; peas and beans being specially subject to their attacks. They are able to complete their growth with a very small amount of nutriment, some of them consuming only a portion a little larger than themselves of a bean or pea. The larvae are fat maggots without legs, but Riley has discovered that the young larvae of _Bruchus pisi_ and _B. fabae_ have, when first hatched, three pairs of legs which are subsequently lost. They also have peculiar spinous processes on the pronotum. Both of these characteristics may be correlative with the transient differences in the activities of the larva, for the little creature is not at first located in the pea, but mines a gallery in the pod, in which it moves about, subsequently entering the pea and losing its legs. There is a good deal of difference in these respects between the two species—_B. pisi_ and _B. fabae_—examined by Riley, and as but little is known of the life-histories of other Bruchidae it is probable that still greater variety prevails. Heeger has found that _Bruchus lentis_ sometimes requires two seeds to enable it to complete its growth; it is, notwithstanding its legless state when half-grown, able to migrate by dropping to the earth, and dragging itself along by its mandibles till it comes to another pod into which it bites its way. [Illustration: Fig. 141—_Bruchus pisi_ or pea-weevil. A, Young larva; B, prothoracic spinous process; C, post-embryonic leg, greatly magnified; D, pea-pod, with tracks of entry; E, portion of pod, with egg, and the subsequently formed track, magnified; F, imago. (After Riley.)] The family has, until recently, been placed in the {278}Rhynchophorous series, with which it has, however, no direct connection. On the other hand, it is so closely connected with Chrysomelidae that it is not possible to indicate good characters to distinguish the two at present. The Australian genus _Carpophagus_, and the large South American species of _Caryoborus_ appear to be quite indistinguishable as families, though Lacordaire and Chapuis placed one in Bruchidae, the other in Chrysomelidae. The definition we have given applies, therefore, to the majority of the family, but not to the aberrant forms just mentioned. The European genus _Urodon_ appears to belong to Anthribidae, not to Bruchidae. The family Bruchidae is called Mylabridae by some.