. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 50 can live for a long time upon leaves alone when squares and bolls are wanting. Bolls are only slighth^ attacked so long as there is an abundance of clean squares. The method of feeding is alike in both sexes. The mouth parts are very flexibly attached at the tip of the snout (fig. 2) and are capable of a wide range of movement. The head fits smoothly into the prothorax like the ball into a socket joint and is capable of a con- siderable angle of rotation. The proboscis itself is used as a lever in prying, and
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 50 can live for a long time upon leaves alone when squares and bolls are wanting. Bolls are only slighth^ attacked so long as there is an abundance of clean squares. The method of feeding is alike in both sexes. The mouth parts are very flexibly attached at the tip of the snout (fig. 2) and are capable of a wide range of movement. The head fits smoothly into the prothorax like the ball into a socket joint and is capable of a con- siderable angle of rotation. The proboscis itself is used as a lever in prying, and helps to enlarge the puncture through the floral envelopes especially. Feeding is accomplished by a combination of movements. The shai-ply toothed mandibles serve to cut and tear, while the rota- tion of the head gives the cutting parts an auger-like action. The foreleg's especially take a YGiy firm hold upon the square and help to bring a strong pressure to bear upon the proboscis during certain portions of the excavating process. The outer layer of the square, the calyx of the flower, is naturally the toughest portion that the weevil has to penetrate, and only enough is here removed to admit the snout. After that is pierced the puncture proceeds quite rapidly, combinations of chiseling, boring, and prying movements being used. While the material removed from the cavity is used for food, the bulk of the feeding is upon the tender, closely compacted, and highly nutritious anthers or pollen sacs of the square. When these are reached the cavity is enlarged, and as much is Fig. 2.—Mexican cotton boll eaten as the w^ecvil can reach. The form of weevil: Head sharing ros- ^^ ^. ^^^^tuY^ bcCOUieS finally like trum with antennae near ^ ^ ^ }/ j middle and mandibles of a miniature flask. ^JriginatP'''^' ^''^^'^'"^ ^"^^ ^^^^^^ weevils have fed considerably do sexual differences in feeding habits begin to appear; from this time on the females puncture mainly the base and
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