50 CAI-IKOUNIA ACADEMY Ol' SflENCES. 



tv|)hl<)sol;ir vessel, whicli is entirely dorsal, is many times smaller than the l()ii<i;itndi- 

 nal dorsal vessel, hut posterior to that somite the typhlosolar vessel assumes a larj^er 

 size, almost eijualliiij^ the main dorsal vessel. In the anterior somites the typhlosolar 

 region does not project down in the intestine, hut is only somewhat wider than the 

 halanee of the intestinal wall. The typhlo.sole in this part appears to he filled with a 

 lihroiis and spongy mass, in which, h(»wever, T have seen no distinct nu(dei (fig. 1:54, 

 c. /•.). The.se cavities are more ohlong at the walls, more round or angular at the 

 center, where several larger cavities are seen. At the upper margin of the typhhj- 

 solc this lihrons hody gives room to Iwn liirgc and scvcial sniallci- longitudinal canals, 

 one at each extremity of the typhlo.sole, all .separated hy muscular fihers or cell-like 

 chand)('rs. Tn fig. loH the fihroiis nature of the interior of the typhlosole is somewhat 

 inoic jironoiinced than it sIkjuUI he, the (ihers appi-aring rather more regular than in 

 reality, though the appearance is always as if the majority of the fihere radiated in a 

 fan-like way from the central s))ongy mass. This |)art of I lie po.sterior typhlo.sole is 

 in c-ross-section deltoid, with the point projecting into the cavity of the intestine 

 (lot), ///). The size of the typhlosole varies with the individual specimen. 



Spermnflieca (figs. cSl to <S(!). There are two |i;iii- of >|i(iniatheea' in viii and 

 i.\ ojH'uing in the intersegmental grooves hetweeu vii and viii and viii and ix. The 

 spermthecal pores are found in front of and slightly outside of the second seta-. As 

 regards the size the spermathecje may he said to he very large, hut unequal, a.s we 

 seldom lind two of the same size. One or two are generally developed at the 

 expense of the others and fill all the availahle space in the somites, frequently pushing 

 the septa into the nearest somites. 8een in a transverse section of a segment the 

 larger spermatheca may he occupying as much as three-fourths of the cavity (fig. 8(i). 

 The spermatheca consists of two distinct parts, of whicli the upper is h^' fai' the largest, 

 rounded in outline or potato-like with comparatively thin walls (fig. 82 <i). This part, 

 though somewhat warty, carries no diverticula and there are no smaller cavities for 

 the storing of the spermatozoa. The lower muscular part is twisted, and setohli(|uely 

 to \\\v foi'mer, hut can in no way he said to form any kind of a diverticulum (figs. 81 

 and 8l2). The muscular layer, which is a direct contiiuiation of the lougitiulinal layer 

 <>! the hody-wall, is only arranged in one way forming a circular muscular stratum of 

 the spermatheca nnich thicker at the hase than at the top (fig. 82 /. m). This nniscular 

 layer extends to the upper part of the .spermatheca (82 a), hut is here quite narrow, 

 'i'he inner glamlular layer is singularly well developed (figs. 82, cjl. c: 84 (jl. ep. and 

 83), projecting inwards in large folds like the epithelial folicles of the inti-stine. 



S(!cretions acciuuuhite ;is n large whitish mass in the upper part of the sperm- 

 atheca, and ai'e seen to he sparingly mixed oi" streaked with spermatozoa. Hut 

 the most characteristic part of the spermatheca is the interlacunary system for the 

 storage of the spermatozoa in the lower or muscular part. A section of this part shows 

 (figs. 82, 83 and 84, /. ,s.) a niw of ehamhers iniliedded heiweeii the epitludial cells, 

 or hetween them and the muscular layer, and which connect more or le.ss directlv 

 with the cavity of the sperniatheea l)v nutans n{ nairnw passages (iig. 8.'> fi.) Some 



