350 
COLEOPTERA. 
seed-coat and so into the seed itself where it feeds upon the tissues. 
The larva is white, curved and with a close resemblance to larvae of 
weevils. Riley showed that, in the first instar, the larva is provided 
with three pairs of incomplete but functional legs, as well as a series 
of thoracic spines and a pair of toothed thoracic plates which enable 
the larva to bore into the pod or seed and so establish itself. When 
it has reached the seed, it moults and appears without the legs and 
the thoracic plates. As a rule, one seed, if full grown, is sufficient 
for a larva (or for many), but in the case of growing seeds the larva 
may eat so fast that the seed cannot develop and it has to move into 
a fresh one. When full grown, the larva cuts a disc in the seed-coat 
almost through and pupates below. When the beetle is ready to 
emerge, the disc readily opens, letting out the perfect insect. In Cary- 
oborus gonagra the larva comes out of the seed and pupates outside 
in an excrementitious cocoon. The beetles are found in the field 
visiting flowers of leguminous plants or on the leaves of plants. They 
appear to take no food, as do the household species also. There is no 
information available on the question of the hibernation, etc., of the 
free-living species. None are pests to crops in India but the house¬ 
hold species are destructive to stored pulse. Bruchid larvae are the 
hosts of Chalcid parasites, which lay their eggs in the larvae in the 
seeds. These insects are sometimes found in abundance in infested 
pulse. 
The family is not a large one and, with the exception of the 
cosmopolitan household species, is principally found in the tropics. No 
list of Indian species exists and there is room for work on this family. 
Including cosmopolitan insects, 37 species are known from India and 
the number of species recorded from the plains is a very small propor¬ 
tion of those there are. The family is divided into two tribes : Urodon- 
tides with clubbed antennae represented by Urodon in Ceylon; Bru- 
chides with dentate or pectinate flattened antennae. The following six 
species of Bruchus include the known or recorded species found in 
stored pulse in India 
(1) B. chinensis, Linn., in Bisum sativum (peas), Dolichos lab-lab 
(val), Dolichos biflorus (moth), Cicer arietinum (gram), Cajanus indicus 
(pigeon pea), Ervum lens (lentil), Vigna catjang (cow pea). 
