They fly about from July till October, living upon the sap of the vine, which is sucked up by the rostrum from the leaves or buds.
Rostrum free, not supported by either the prosternum or the basal segments of the appendages.
Its rostrum is unusually long, being five-sixths of the body length in the female, and slightly shorter in the male.
Within the groove of the rostrum two pairs of slender piercers - often barbed at the tip - work to and fro.
The point of the rostrum is pressed against the surface to be pierced; then the stylets come into play and the fluid food is believed to pass into the mouth by capillary attraction.
The bivalved carapace has a jointed rostrum, and covers only the front part of the body, to which it is only attached quite in front, the valve-like sides being under control of an adductor muscle.
Usually the sides of the carapace are strangely produced into a mock rostrum in front of the ocular lobe, be it oculiferous or not.
This group is characterized by the prolongation of the head into a rostrum or proboscis, at the end of which the mouth, with its appendages, is placed.
The basal portion of the antennae frequently lies in a depression at the side of the rostrum, and this gives the antennae the appearance of emerging half-way along the rostrum.
When the nuts are about half-grown, the female bores, with its rostrum, a minute hole in the still comparatively soft nut-shell, and deposits an egg within the nut.
The capitulum, with its associated structures, is sometimes called the rostrum, whereas sometimes the term rostrum is restricted to the hypostome alone.
The head is seen in front resting on the foot and carrying a median non-retractile snout or rostrum, and a pair of cephalic tentacles at the base of each of which is an eye.
Neither male nor female has wings; the rostrum is replaced by a functionless tubercle; and there is no alimentary canal.
The immense family of the Curculionidae includes members which differ greatly from one another in size, colour, and appearance; even the rostrum, the most striking common characteristic, varies greatly.