CHINESE EARTHWORMS GATES 435 



The clitellum is annular, extending from 13/14 to 16/17; inter- 

 segmental furrows and dorsal pores lacking; no setae visible. There 

 are functional dorsal pores on 13/14 and 16/17. 



The spermathecal apertures are minute, four pairs on 5/6-8/9, on 

 tiny, gi-ayish, transversely oval markings. The intersegmental fur- 

 rows are not visible on one specimen in the vicinity of the spermathe- 

 cal pores. On another specimen the ventral body wall is strongly 

 contracted, making observations on the position of the pores difficult. 

 On the remaining specimen, it appeared at first glance as if the 

 spermathecal apertures were on the anterior margins of segments 

 vi-ix. But this appearance is probably due to the stronger develop- 

 ment of a demarcating furrow at the anterior border of the pore 

 tubercle than at the posterior border. When the spermathecal duct 

 is pulled out from the parietes, as may easily be done, the oval area 

 is removed, leaving an aperture with a smooth rim in the body wall 

 that does not belong to one segment more than another. As the pore 

 is at the center of this area it is regarded as intersegmental. 



The male apertures are minute, each pore located at the center of 

 a circular or slightly oval (transversely) disk that is clearly marked 

 off from the parietes by a slight furrow. The disks are 2-3 intersetal 

 intervals wide transversely or about 0.5 mm. 

 There are no genital markings. 



Internal anatomy. — Septa 5/6-7/8 are thickly muscular; 8/9 is 

 present and complete though membranous, bulged posteriorly into a 

 funnel-shape by the gizzard, and attached centrally to the esophagus 

 anterior to the hearts of ix; 9/10 lacking; 10/11-13/14 thickly mus- 

 cular, especially the first three. 



The intestine begins in xv. The intestinal caeca are simple, con- 

 stricted by the septa through which they pass. 



The last pair of hearts is in xiii. All hearts of ix-xiii pass into the 

 ventral blood vessel. 



The testis sac of xi is horeshoe-shaped (Tatsienlu specimens) on 

 the anterior face of 11/12. The ventral ends of the sac are not in 

 contact beneath the esophagus, and no communication between the 

 ventral ends was found. The hearts of xi are contained within the 

 testis sac and are surrounded by testicular material. A section of the 

 dorsal blood vessel belonging to xi is also contained within the testis 

 sac but is not surrounded by testicular material. The seminal vesicles 

 of xi, small, vertical bodies are not contained wdthin the testis sac 

 but are just lateral to the outer wall of the sac. So far as can be 

 determined from the material available, the testis sac of x is similar 

 to that of xi, and contains the hearts of x. The testis sacs of the Dawei 

 specimen are paired, ovoidal. The anterior sacs project anteriorly 



