. Appendix to the Journals of the Senate and Assembly of the ... session of the Legislature of the State of California . segments immediately back of the head. These segments are namedpro-, meso- and metathorax. The first, or the one connecting with thehead, being the prothorax, the middle section the mesothorax, and thelast, the one connecting with the abdomen, being the segments appear to be solid rings, but really they are composed 52 REPORT OF THE COMMISSIONER OP HORTICULTURE. of several hexagonal plates, capable of motion and to which the variousappendages are articulated
. Appendix to the Journals of the Senate and Assembly of the ... session of the Legislature of the State of California . segments immediately back of the head. These segments are namedpro-, meso- and metathorax. The first, or the one connecting with thehead, being the prothorax, the middle section the mesothorax, and thelast, the one connecting with the abdomen, being the segments appear to be solid rings, but really they are composed 52 REPORT OF THE COMMISSIONER OP HORTICULTURE. of several hexagonal plates, capable of motion and to which the variousappendages are articulated. Each of these segments bears one pair oflegs, but only the meso- and metathorax bear wings, and either or bothpairs of wings may be wanting; as in the flies there is but one pair,and in many insects none. Legs.—In most adult insects and many larvae, each of the threethoracic segments bears one pair of legs, composed of several joint immediately attached to the body is knownas the coxa, the next as the trochanter, femur, tibia, andtarsus, the latter corresponding to the foot in the higher C Set Sc2 tb. M FIG. 18. Leg of abeetle (Caloso-ma calidum). c,coxa; el, claws;/, femur; s, spur;tx-P, tarsal seg-ments; tb, tibia;tr, trochanter. 3dA 2dA tstA FIG. 19. Hypothetical type of venation. A, anal vein; C, costa; Cu,cubitus; M, media; R, radius; Sc, subcosta. (After Comstock andNeedham.) animals. The legs are modified in many ways to meetthe requirements of the insect, and are adapted to run-ning, leaping, swimming, burrowing, or grasping their
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Keywords: ., bookauthorcaliforn, bookcentury1800, bookdecade1850, bookyear1853
