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HANDBOOK OF INVERTEBRATE ZOOLOGY. 



white, membraneous pouch (Fig. 85, g), which extends 

 across the median ventral floor of the tenth and eleventh 

 segments, and receives the testes of both sides of the 

 body. 



c. On the lower surface of this organ, near the median 

 line, are the four ciliated, funnel-shaped openings of the 

 vasa deferentia (Fig. 85, h), one on each side in the tenth, 

 and one on each side in the eleventh segment. They are 

 bound by connective tissue to the lower surface of the 

 seminal vesicle, but have no communication 

 with its cavity. The male fluid escapes 

 from the receptacle by the rupture of its 

 walls, and is then drawn by the cilia into 

 these funnels. 



Fig. 87. — Anterior portion of nervous system of 

 earthworm. (From Lankester, Anatomy of the Earth- 

 worm, Quar. Jour. Mic. Sc, N. S., vol. V. P. vi., 

 Fig. 6. ) Magnified about five diameters. 



a. Commissural fibres, b, b, b, b. The two pairs of 

 nerves which arise from each ganglion, c, c. The nerves 

 which pass from the commissure to the diaphragm. 

 5, 6, 7, 8. The ganglia of the fifth, sixth, seventh, and 

 eighth segments, respectively, d. (Esophageal collar. 

 f e. Nerves from collar to the nmscles of fourth segment. 

 /. Space occupied by pharynx, g. Nerves to pharynx. 

 h. Cerebral ganglia, i. Nerves to first segment. 



Fig. 87. 



d. The vasa deferentia may be traced as delicate, white 

 tubes running backward from the funnels (Fig. 85, k). 

 The four tubes are at first separate, but in the thirteenth 

 segment the pair on each side unite, and thus form two 

 ducts, which run backward lietween the inner ends of the 

 two rows of setae of each side, and open externally in 

 the fifteenth seofment. 

 . e. The seminal receptacles; four nearly spherical, vas- 



