52 CALIFORNIA ACADEMY OF SCIENCES. 



Siyermduds and jirotifates (figs. 103 to 113). Tliere are two pair of sperm funnels 

 and ducts, the ducts joined together. The ciHated rosettes or sperm funnels are 

 found in x and xi. The anterior pair is engaged in the sperm-sac of that somite 

 (fig. 97), while the posterior pair is generally free (fig. 98). T have, however, seen 

 the s])erm-sacs attached to the funnels in these somites in some specimens, and there 

 appears in this respect to be considerable variation; generally, however, the rosettes 

 are free (fig. 98) in somite xi. Also with the anterior funnel there is some variation, 

 lu some specimens the funnels were entirely enclosed in the sperm-sacs, in others the 

 sperm-sac was merely attached to the free surface of the funnel, while in others again 

 one-half of the funnel was imbedded in the sperm-sac, while the other half was free. 

 Figs. 97 and 98 show cross-sections with the sperm funnels or ciliated rosettes free or 

 imbedded. 



The spennduds join in xii and continue in a direct line to the prostate, which 

 they enter in somite xviii. The point of junction is in the lower part of the glandular 

 part close to the muscular duct (fig. 86, e.). The duct runs between the very thick 

 vascular layer and the longitudinal muscular hu'er of the body (figs. 117 and 118, sp.). 

 The two ducts are never fused together, but continue distinct and separate, though out- 

 wardly joined, as to the very entrance in the muscular part of the prostate (figs. 112 

 and 113). While the junction of the spermduct and the prostate is, to all appearances, 

 in the glandular part of the prostate (figs. HO and 113), the real point of entrance is 

 in the muscular duct (fig. 113, upd.). After having touched the glandular ])art, the 

 spermducts bend and cross the intervening space to the muscular 2)rostate which they 

 enter in a slanting direction, then passing considerably downward enclosed in the 

 muscular part of the prostate, before entering the lumen proper (figs. 100, 107, 110, 

 111, 112, 113). Fig. 113 represents a cross-section in which the spermducts have 

 been cut twice. Part of the spermduct is seen free close to the glandular part of the 

 prostate, part again is seen just at the fusion of the ducts with the lumen of the 

 muscular part. The duct closest to the lumen has been partly differentiated, the cells 

 having lost their nuclei. 



The prnatate consists of a very large cylindrical, but greatly coiled, duct (figs. 

 106 and 107 and 1), which generally lies pressed flat to the body wall of xviii (fig. 86, 

 pr.) It opens outwardly in xviii in the posterior part of the somite in the same pore 

 as the penial setse. 



There are two layers of cells in the glandular part, but apparently no muscular 

 layer between them. The outermost layer consists of large glandular lobes containing 

 glandular cells which pass between the inner cell layer, and discharge in the lumen of 

 the prostate (see figs. 108 and 109). There is a large S3^stem of blood vessels which 

 penetrate both of the cellular layers, but which is not developed to the same extent as 

 in Deltania. 



lu cross-section of the body-wall (fig. 103 ^1) the prostate is seen to open 

 laterally to the penial settle, though in the same pore, situated at the very junction of 

 the glandular clitellum and the ventral zone {v- p-) of the body (fig. 103 A. i ). 



