Entomology for beginners; for the use of young folks, fruitgrowers, farmers, and gardeners; . t the end of the abdomen. Theseseventeen segments, moreover, are grouped into three re-gions, four composing the head, three the thorax, and tenthe hind-body, or abdomen. On examining the abdomen,it will be found that the rings are quite perfect, and thateach segment may be divided into an upper (tergal), a lateral(pleural), and an under (sternal) portion, or arc (Fig. 1, A).These parts are respectively called tergite, pleurile, andsternite; while the upper region of the body is called thetergum, the
Entomology for beginners; for the use of young folks, fruitgrowers, farmers, and gardeners; . t the end of the abdomen. Theseseventeen segments, moreover, are grouped into three re-gions, four composing the head, three the thorax, and tenthe hind-body, or abdomen. On examining the abdomen,it will be found that the rings are quite perfect, and thateach segment may be divided into an upper (tergal), a lateral(pleural), and an under (sternal) portion, or arc (Fig. 1, A).These parts are respectively called tergite, pleurile, andsternite; while the upper region of the body is called thetergum, the lateral the pleurum, and the ventral or underportion the sternum. As these parts are less complicated in the abdomen, wewill first study this region of the body, and then examine themore complex thorax and head. The abdomen is a littleover half as long as the body, the tergum extending far THE STRUCTURE OF INSECTS. 3 down on the side and merging into the pleurum withoutany suture or seam. The pleurum is indicated by the rowof spiracles, which will be noticed farther on. The sternum Tarsus. FIG. anatomy of Caloptfnus spretus, the head and thoraxdisjointed.—Kingsley del. 4 ENTOMOLOGY. forms the ventral side of the abdomen, and meets the pleu-rum on the side of the body. In the female (Fig. 1, B} the abdomen tapers some-what toward the end of the body, to which are appendedthe two pairs of stout, hooked spines, forming the oviposi-tor (Fig. 1, B, r, r). The anus is situated above the upperand larger pair, and external opening of the oviductis situated between the smaller and lower pair of spines;it is bounded on the ventral side by a movable, triangularacute flap, the egg-guide (Fig. 1, B, eg, and Fig. 4). The thorax, as seen in Fig. 1, consists of three seg-ments, called the prothorax, mesothorax, and metathorax, orfore, middle, and hind thoracic rings. They each bear apair of legs, and the two hinder each a pair of wings. Theupper portion (tergum) of the middl
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Keywords: ., bookcentury1800, bookdecade1880, bookpublishe, booksubjectinsects
