;)2 n.M.Il-OKNIA ACADK.MY DK SCIKNCES. 



S/ti'r))idiiiis Mid j/rn^lnti's (lij;s. lOo to 113). There are two pair of .sperm fiiiinel« 

 and iliuts, the iliict.s joined toj^ctlicr. The ciliat(;(l rosettes or s|ierin fiiiiiiels are 

 t'ouiul ill \ and xi. The; anterior pair is engaged in ihe speiin-siic of that .somite 

 ((ig. {)7), while the posterior pair is generally free (fig. !)rS). I have, however, seen 

 the sperm-.-acs uttacdied to the fiiniicls in lhe.se somites in some speeimeiis, and tliere 

 appears in this res|)ect to lie coiisidcrahh' variation; generally, however, the roseltes 

 are free (lig. !><S) in somite xi. Also with the anterior funnel there is .some variation. 

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

 spernj-sae was meri-ty attaetie<l to the free surface of the funnel, wiiile in others again 

 one-half of the funnel was imheddt'd in the sj)erin-sae, while the other half was free. 

 I'^igs. !<7 and i'.S show eross-seetions with the sperm funnels or ciliated I'osette.s free or 

 imiiedded. 



The sjirnji(liir/fi join in xii and eontiniu' in a dinet line to the pi'cjslale, which 

 they enter in s(miite xviii. The point of junction is in the lower part of the glandular 

 pari close to llie nuisculai- duct (fig. 80, e.). The duct runs hetween the very thick 

 vascular layer and the longitudinal mu.seular layer of the body (figs. 117 and 118, .sy>.). 

 The two duets are never fused together, hut eontiinie distinct ami separate, though out- 

 wardly joined, as to the very entrance in the muscular part of the prostate (ligs. J 12 

 and 1 lo). While the junction of the .spermduct and the prostate is, to all appearances, 

 in the glandular jiart of the ])rostate (figs. IK) and 11^!), the real point of entrance is 

 in the muscular duct (fig. 113, ><ji<J.). After having touched the glandular part, the 

 spermducts heiid and cro.ss the intervi-ning s])ace to the muscular pnjstate which they 

 enter in a slanting direction, then passing consich'rahly downward enclosed in the 

 muscnlar part of the prostate, before enlt'ring the Innieii proper (ligs. 1()C>, |(I7, IIK, 

 ill. III', 113). Fig. Il^) represents a cross-section in which the spermducts have 

 been cut twice. Part of tlu; spermduct is seen free clo.se to the glandular part of the 

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

 mnseular jtart. The ductclosesl to the humii ha.s been partly diflterentiated, the cells 

 having lo.st their nuclei. 



The jiiiixhilc consists of a very large cylimlrical, Iml greatly coiled, duel (ligs. 

 IdC, and 107 and 1 I. which generally lii's pressed Hat to the imdy w;ill of xviii (lig. ^i\, 

 jir.) ll opens outwardly in xviii in thi' posterior part of the soniile in the same pore 

 as the penial setic. 



There are two layers of cells in the glandular pari, Iml appannlly no inn>iular 

 layer between them. 'I'lie outermost layer consists of large glamlnlar lobes c((niaiiiing 

 glandular c(dls which pa.ss between the inner cell layer, and discharge in the lumen of 

 the prostate (see ligs. 108 and 10!>). There is a large systi'in of blood vessels which 

 [lenelrate both of the cellular layers, but which is not developed to the .same I'Xtcnt as 

 in Deltania. 



In cross-.section of the body-wall (lig. 103 .1) the prostate is seen to open 

 laterally to the penial seta', though in tln' same pore, situatcfl at the very jnnclion of 

 the glandulai- elilelluui and (he ventral zone (''./'.) of the body (lig. lOi! .l.>5). 



