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Make a drawing of one of the cephalic legs. 



The same parts may be traced on each of the other legs. 



Wings. — The wings are plate-like or membraneous ex- 

 pansions of the body-wall. Each wing is traversed by many 

 linear thickened portions ; these are termed vei?is or nerves. 

 The principal veins extend proximo-distad. These are joined 

 together by many smaller cross-veins. The thin parts cir- 

 cumscribed by the veins and cross-veins are called cells. 



The two pairs of wings of a locust differ remarkably in 

 form and texture. 



Mesothoracic wings {tegmind). — The mesothoracic wings are 

 long, narrow, and of a parchment-like texture. They are 

 termed tegmina, 



Metathoracic wings. — The metathoracic wings are much 

 larger and of more delicate texture than the first pair of 

 wings. When not in use they are folded in plaits like a fan 

 and concealed by the tegmina. Some writers who designate 

 the mesothoracic wings as tegmina or wing-covers, describe 

 the metathoracic wings simply as the wings. 



PARTS OF THE ABDOMEN. 



Number of segments — There is a difference of opinion 

 as to the number of segments in the body of a locust. The 

 difficulty arises from the complexity of the caudal end of 

 this region, and the fact that some authors have considered 

 the first abdominal sternum as a part of the metathorax. 

 Eight abdominal segments can be readily distinguished in 

 the female , and nine, in the male.* Caudad of the eighth 

 abdominal segment of the female and the ninth of the male 



* If a sufficiently large series of specimens of the red-legged locusts be exam- 

 ined it will be seen that there are two kinds , one. in which the caudal part of 

 the body tapers to the end, and bears four, pointed and curved, horny pieces ; 

 and another, in which the caudal part of the body increases in size caudad 

 and is terminated by a single, large, hood-shaped plate. The former is the 

 female , the latter, the male 







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