BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 27. AFD. IV. NIO 6. 17 



but a closer investigation, especially on longitudinal sections, 

 reveals the fact that they are due to considerable bundles of 

 extremely fine filaments running in a longitudinal direction 

 and Crossing the interstices between the pointed lower ends 

 of the ciliated cells. In horizontal sections across the colum- 

 nar cells it is stated with certainty that the "bodies" above 

 mentioned are nothing else than transversely cut bundles of 

 very fine threads. In such preparations stained with iron- 

 hffiuiatoxyline, the cells present themselves as scattered black 

 points surrounded by the crossing bundles of filaments. As 

 to the nature of the bundles it is of course impossible, for the 

 present, to pronounce any exact idea. However. though it 

 may seem stränge, I am inclined to consider them to be peri- 

 pheral distributions of nerves between the bases of the cilia- 

 ted epithelium cells. 



On the left side of the efferent duct and imbedded in its 

 layer of connective tissue is to be observed a wrinkled and 

 plaited cord-like formation extending from the upper and 

 anterior end of the genital basis, where it communicates with 

 the lumen of the issuing duct, forwards to that part of the 

 duct where it meets the madreporic canal and bends upwards 

 in order to open exteriorly. Just at the curvation, the cord 

 terminates in ä small enlargement. It is easily brought into 

 view^ by treatment with hsematoxyline, fuchsine, carmine or 

 other Solutions. Seen in toto under a low magnifying power, 

 it presents the view of a simple wrinkled band or cord, hence 

 the name germinal cord (comp. the wood-cut on page 7). 



In sections across the efferent duct it becomes obvious 

 that its left wall is often somewhat thicker than the right 

 and, besides, is provided with some low ridges or folds pro- 

 truding into the lumen, one of these being as a rule more 

 prominent. Sometimes I also observed such a low longitudi- 

 nal elevation on the outer left side. In some very few cases 

 the ridges in question are almost imperceptible, probably owing 

 to a high degree of extension. 



Moreover, when examining the sections carefully, it be- 

 comes evident that the germinal cord is by no means a solid 

 string, but that, on the contrary, it presents a more or less 

 complicated arrangement, built up either of a single very 

 meandrous canal, or of several limited cylindrical and elonga- 

 ted cavities, always lined with rather large primitive germi- 



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