29 



lo-ventral angle of each pleurum there is a spiracle. The 

 sterna are well developed and are separated from the pleura 

 by a narrow, involuted, membraneous part. 



Caudal part of abdomen of female. — The most promi- 

 nent portion of the caudal part of the abdomen of the 

 female is the ovipositor. This is an organ consisting of four, 

 strong, curved, and pointed pieces, which form the most 

 caudal part of the body. With this organ the insect makes a 

 hole in the ground in which she lays her eggs. This is done 

 by alternately bringing together and separating the two pairs 

 of pieces, and at the same time pushing the body into the 

 ground. Examine carefully these pieces, and note how well 

 they are adapted to this purpose. 



Between the ventral pieces is the opening of ike oviduct. 



Ventrad of this opening and also between the ventral 

 pieces of the ovipositor is a pointed prolongation of the 

 eighth abdominal sternum ; this has been termed the egg- 

 guide. Dorsad of the egg-guide there is a forked organ 

 which also is used in placing the eggs. 



The ventral pieces of the ovipositor are supported by two 

 pairs of sclerites ; there being a sclerite closely applied to 

 the ventral surface of each pair, and one to the lateral sur- 

 face of each. 



The ninth and tenth abdominal terga are shorter than any 

 of the preceding abdominal terga and are joined together on 

 each side, the lateral parts of the suture separating them 

 being obsolete. 



Caudad of the tenth tergum there is on the middle of the 

 back a shield-shaped piece ; this is believed to represent an 

 eleventh segment. It consists of two sclerites, as is indi- 

 cated by a transverse suture. 



On each side, projecting from beneath the caudal border 

 of the tenth tergum, is a pointed appendage • these are the 

 cerci. 



