THe INSEcT FAUNA OF THE GENUS CRATAEGUS 1069 
sufficient to say that A. nebulosus is a brown or grayish oval beetle, from 
3.75 to 4.25 millimeters long, generally with a whitish, V-shaped mark 
on the fore part of the elytra, with a long, slender, curved beak, and the 
front femur having two teeth on its apical part, one large and the other 
small (Plate LX XIV, page 1070). 
The species has been found in New York, New Jersey, Michigan, 
Indiana, Missouri, Arkansas, and Louisiana, and therefore it seems 
probable that it is present wherever its hosts are found east of the Rocky 
Mountains. Although Dietz considers this specics to be more charac- 
teristic of the European fauna than of our own, no record can be found of 
its occurrence in Europe or elsewhere outside of this country. 
Its hosts include a number of the larger-flowered species of hawthorns, 
such as Crataegus punctata, C. brainerdi, C. pruinosa, and C. mollis. The 
smaller-flowered species, such as C. oxyacantha, are not selected by the 
beetles for oviposition, probably because there is not space enough for 
the full development of the larva within the bud. 
The injury caused by the hawthorn blossom weevil is most apparent 
while the trees are in full bloom. At that time the infested blossoms are 
brown and remain closed. On badly infested trees fully fifty per cent of 
the blossoms may be in this condition and the trees present a scorched 
appearance. As the young fruit begins to set, the infested blossoms com- 
monly fall to the ground, but they may sometimes be seen on the trees 
even after the beetles have emerged in June. 
The beetles come out of hibernation and appear on the branches of the 
hosts about mid-April, feeding ravenously on the buds, which are showing 
ereen. It is not uncommon to see a beetle with feet braced and beak 
inserted up to the eyes in a bud while it hurriedly eats the tender leaves 
within. As soon as all the food within reach of the entrance hole is eaten, 
the beetle seeks another bud on the twig and repeats the process. The 
puncture inthe bud is round, is 0.3 millimeter in diameter, and turns 
dark as soon as the beak is withdrawn. The presence of the beetles may 
be detected by these dark round holes in the buds before the egg-laying 
period arrives. The beetles continue to feed on the buds during suitable 
weather until the clusters have separated enough for oviposition in the 
blossoms. 
During cool weather the beetles remain inactive, generally in the axils 
of the twigs with their heads down. A few observations on the relation 
of temperature to their activities were made, and these indicate that 
the beetles remain inactive while the temperature is below 50° F. The 
optimum temperature is from 60° to 70°, and when it is raised to 78° 
the beetles rush about like mad, attempting to oviposit in every bud. 
Under most conditions they seem reluctant to fly, but when placed on 
distasteful food they fly away. They continue their activities on cloudy 
or rainy days and at night if the temperature is sufficiently high. 
a 
