iyo 



MORPHOLOGY OF INVERTEBRATE TYPES 



latter terminates in a wide, slit-shaped genital opening situated 

 in the genital groove on the ventral surface of the abdomen. It 

 belongs to the second abdominal somite. Above the genital 

 opening is a chitinous structure called epigynum with two open- 



iRs. 



o.. 



FIG. 33. Female reproductive organs of a spider, modified from V. v. 

 Engelhardt. ov, ovary; o, oviduct; , uterus; co, copulation opening; cd, 

 copulation duct; gp, genital opening; F, fertilization canal; I, II, III Rs, 

 first to third sperm receptacles. 



ings leading into as many sperm receptacles. Thus there are alto- 

 gether three sexual openings. A fertilization canal connects each 

 receptacle with the uterus. Only the two openings leading into 

 the receptacles are used for copulation. The sperm is stored 

 for a considerable time in the receptacles. As the eggs pass the 

 openings of the fertilization canals in the uterus, they are 



