140 ENTOMOLOGICAL NEWS. [November, 



use. The long abdomen was bent under the thorax and between 

 the legs, and the thrusts were made straight in front of the face. 

 As the abdomen was brought forward the short ovipositor pointed 

 straight in front like the index finger. See illustration. 



The larvae when pierced did not drop to the ground, but threw 

 their heads higher in the air and ejected a dark colored liquid. 

 So far as I saw but one egg was deposited in each. 



-o- 



ELEMENTARY ENTOMOLOGY. 



Fifth Paper. THE THORAX, THE LEGS. 



The second region of an insect's (imago's) body is the thorax. 

 To it are usually attached three pairs of legs and two pairs of 

 wings. It is composed of three segments. The first segment, 

 articulating with the occiput in front, is the prothorax, which 

 bears the first pair of legs. The second segment is the mesothorax, 

 bearing the second pair of legs and the first pair of wings. The 

 third segment is the metathorax, bearing the third pair of legs 

 and the second pair of wings. 



Typically, each segment of the thorax consists primarily of 

 four parts, a dorsal part (tergum- or notum), a ventral part (ster- 

 num}, and on each side, between the tergum and the sternum, a 

 pleurum* 



The prefixes pro-, me so- and meta- are used before notuni and 

 sternum to denote the notum and sternum of the prothorax, 

 mesothorax and metathorax respectively. 



' ' The tergum of each thoracic segment is composed typically 

 of four sclerites. These are arranged in a linear series. They 

 are named, beginning with the first or most cephalic, prtzscutum, 

 scutum, scutellum and post-scutellum. In the prothorax the su- 

 tures between these four sclerites are in many cases obsolete, the 

 pronotum appearing to be composed of a single sclerite. In 

 beetles and bugs the scutellum of the mesothorax is usually quite 

 conspicuous, appearing as a more or less nearly triangular piece 

 between the first pair of wings at their base. ' Most entomological 



* Tergum, sternum and pleurum, with their adjectives tergal, sternal and pleural are 

 sometimes used to denote respectively the dorsal, ventral and lateral parts of the entire 

 body of an insect. In such cases the terms tergite, sternite and//t'r/te, are applied to the 

 dorsal, ventral and lateral parts of each segment. 



