42 



ART. 4.— EKITARO NOMURA 



Its wall consists of two layers, an inner of regularly arranged, 

 ciliated, columnar cells and an outer of connective tissue. The 

 nuclei of the inner epithelium is situated basally, and the plasmic 

 strands are very feebly developed. 



b. Vas deferens. The funnel is continued into a very long 

 narrow vas deferens, which undergoes several windings. It is 

 circular in cross-section and is of the same calibre through its 

 whole length. The structure of the wall is nearly the same as 

 in L. gotoi, except that the plasmic strands are very numerous 

 and compact, and the nuclei less elongated. 



c. Atrium. It is the enlarged portion of the sperm- duct 

 and receives the vas deferens at one end. Its wall consists of 

 three layers : an outer of connective tissue, a middle of muscle 

 fibres, and an inner of large glandular cells. 



B 



Fig. 31. 



L. willeyi. Prostate gland and related portions. A — from a living specimen. 

 B — cross section through the opening of the prostate, atr — atrium, ad — atrial duct- 

 portion, opr — opening of the prostate gland into the atrium, pr — prostate gland, 

 vd — vas deferens. 



cl. Duct portion. The duct portion is longer than the atrium 

 proper, and is of the same structure as in L. gotoi except that 

 the inner layer is ciliated. 



e. Prostate. The prostate gland is somewhat spindle shaped 

 and opens widely into the broadest part of the atrium. Its 

 minute structure is the same as in L. gotoi. 



/. Penis. It is enclosed by a chitinous sheath and projects 

 into the penial chamber, formed by the invagination of the body 

 wall. The wall of the penis consists of two layers, the outer of 

 which is a direct continuation of the lining epithelium of the 

 penial chamber, and the inner, which is not ciliated, of the inner 



