230 HANDBOOK OF INVERTEBRATE ZOOLOGY. 



open into the oviduct, close to its termination. The eggs 

 are fertilized while passing this opening on their way out 

 of the oviduct. 



V. The Examination of the Male. 



The males are very rarely found, but they may occa- 

 sionally be captured while copulating with the females. 

 They are very much smaller than the females, and they 

 difl'er from them in the following respects : — 



a. The first antennae are more stout than those of the 

 female, and near the tip of each there is a hinge-joint, 

 which allows the terminal portion to fold down onto the 

 basal portion, like a knife-blade shutting into its handle. 

 These antennae are the clasping organs, by which the male 

 clings to the abdomen of the female. 



6. The male abdomen is made up of five somites, of 

 which the first and second correspond to the first segment 

 of the female abdomen. 



c. The reproductive organs of the male consist of a sin- 

 gle median testis, and two long winding vasa deferentia. 



1. The testis (Fig. 123, t) is a small compact transpa- 

 rent body on the median line, above the digestive tract, 

 under the posterior edge of the carapace. It is divided, 

 at its anterior end, by a notch, into two divergent 

 branches, each of which is continued to form, — 



2. The vas deferens: a long folded tube (Fig. 123, vd^ 

 divided into three regions. 



(i.) The first division (123, vd. 1) is a delicate transpa- 

 rent tube, with a thick wall, and a very small central 

 cavity. It runs downwards and backwards to the second 

 or third thoracic somite, and then bends forwards again 

 nearly to the anterior edge of the testis. These two 

 bends are bound up in a single sheath. The cavity of this 

 portion of the vas deferens, which is simply a duct to 



