2 ENTOMOLOGY. 



without its suffering any pain, by throwing it into a bottle 

 containing cotton saturated with ether. It may when dead 

 be taken out of the collecting-bottle and dried. It is most 

 convenient to pin it. This may be done by thrusting a 

 slender insect-pin through the collar. For class use it is 

 better to preserve a lot of grasshoppers in alcohol; before 

 using them they can be soaked in water to take out the 

 alcoholic odor, and can then be easily handled without 

 being pinned, and the wings unfolded or the mouth-parts 

 and legs moved without their breaking off. 



External Anatomy. On making a superficial examination 

 of the locust (Caloptenus femur -rubruvri), or the Rocky 

 Mountain locust (C. spretus), its body will be seen to con- 

 sist of an external crust, or thick, hard integument, pro- 

 tecting the soft parts or viscera within. This integument 

 is at intervals segmented or jointed, the segments more or 

 less like rings, which, in turn, are subdivided into pieces. 

 These segments are most simple and easily comprehended 

 in the abdomen or hind-body, which is composed of ten of 

 them. The body consists of seventeen of these segments, 

 variously modified and more or less imperfect and difficult 

 to make out, especially at each extremity of the body 

 i.e., in the head and at the end of the abdomen. These 

 seventeen segments, moreover, are grouped into three re- 

 gions, four composing the head, three the thorax, and ten 

 the hind-body, or abdomen. On examining the abdomen, 

 it will be found that the rings are quite perfect, and that 

 each 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, and 

 sternite; while the upper region of the body is called the 

 tergum, the lateral the pleurum, and the ventral or under 

 portion the sternum. 



As these parts are less complicated in the abdomen, we 

 will first study this region of the body, and then examine the 

 more complex thorax and head. The abdomen is a little 

 over half as long as the body, the tergum extending far 



