64 LABORATORY DIRECTIONS 



4. Parietal vessels may be found in the body wall and 

 in the wall of the intestine. 



5. Make a diagram of the main trunks of the circulatory 

 system. Number the body segments shown. 



REPRODUTIVE SYSTEM 



In studying this system be careful to prevent injury to the 

 organs of other systems. 



A. Male Reproductive Organs 



1. Three pairs of sperm sacs, large white sacs at sides of and 

 above esophagus. Some of them may not be very large because 

 the specimens were not at the height of sexual activity when 

 killed. Three pairs, in which somites? They contain sperma- 

 tozoa. 



2. Ventrally the sperm sacs are connected by a common 

 seminal vesicle. 



3. The testes, two pairs in X and XI, in positions corre- 

 sponding to those of the ovaries in XIII, are small and being en- 

 closed in the seminal vesicle they cannot be seen. 



B. Female Reproductive Organs. 



1. The ovaries are attached to the anterior septum of XIII 

 near the mid-ventral line. They are generally difficult to find. 



2. Oviducal funnels are on posterior septum of XIII oppo- 

 site the ovaries. 



3. The oviducts lead from them backwards to the ventral 

 wall of XIV. 



4.' Spermathecae, two pairs of small globular sacs lying 

 close to the septa between IX and X, and X and XL They open 

 to exterior on ventral side and receive spermatozoa from another 

 worm. 



