THE SIAMESE GRAIN BEETLE. 17 
Prothorax in the shape of a transverse rectangle somewhat out of proportion, pale 
and shiny. Mesothorax and metathorax transverse, wider than the prothorax but 
both together hardly exceeding it in length. Pale, more or less unequal, the sides 
somewhat curved. 
Abdomen more or less enlarged, somewhat rounded at the sides of segments, and 
narrowing to the rear. Of the nine segments, the first eight are shining dirty-white, 
short, more or less uneven, folded transversely and surmounted by four longitudinal 
rows of swellings or scars, the lateral rows of which are less pronounced. The ninth 
is a little narrower, provided on the back with a large flattened plate, which is received 
in a broad hollow on the eighth segment, fulvous, rugulose or folded transversely for 
about the first third, and broadly hollowed upon the summit, the deepest part of the 
hollow armed with a median angular or conical tooth, and limited by the two strong 
hooks, darker in color and with the points recurved upward and inward. 
Beneath the body is pale, subdepressed, sparsely hairy, more or less uneven, with 
the underside of the head and the last ventral arch fulvous. 
Feet short, pale, terminating in a small hard hook, almost straight, brownish. 
Length 5.35 mm.; width 1.07 mm., of head 0.50 mm. 
Measurements from fully mature, freshly killed specimens extended 
full length. 
THE PUPA. 
The pupa has not been described and no material is at present 
available for descriptive purposes. The general appearance of the 
pupa, however, is well shown in the accompanying illustration (fig. 
2, d). In life it is of the same whitish color as the larva and like 
the larva, also, its last segment terminates in two processes, slightly 
incurved. 
It measures about 2.7 mm. in length and 1 mm. in width. 
DISTRIBUTION. 
There is now practically no doubt that the species is firmly estab- 
lished in this country, both in North America and in South America, 
and that it is cosmopolitan in a somewhat narrow sense, apparently 
being restricted to the tropical and to the warmer temperate zones 
corresponding to the Lower Austral of North America. 
Since this species was first observed by the writer in a Siamese 
grain exhibit, and as it appears to be well established there, it may be 
known as the Siamese grain beetle. 
HABITS. 
Writing of this species in 1888, M. Claudius Rey stated that he 
discovered the larvse in company with the adults in a shipment of 
soy beans (Soja hispida), which were in most part reduced to powder, 
and which came from Saigon, Cochin China. He remarked that M. 
Yalery Mayet had collected the same species at Marseille, France, in 
peanuts, and that the beetle had been captured flying on the mari- 
time coast where he surmised it would probably some day become 
