268 FRANK E. PEDDAED. 



tory tubes would almost decide the matter of their being 

 independent organisms. 



§ Internal Anatomy. 

 The reproductive organs are peculiar in a few respects ; not, 

 however, the testes and the sperm-sacs : the former occupy the 

 usual segments in -which those gonads lie, viz. 10th and 11th. 

 The sperm-sacs are voluminous ; they extend from the 9th to 

 the 12th segment. The sperm-ducts open into Segments 10 

 and 11 by large folded funnels. The tubes connected with 

 these plunge at once into the thickness of the body-wall, and 

 the two tubes of each side fuse. The single sperm-duct thus 

 formed passes back still embedded in the body-wall near to 

 the junction of the circular with the longitudinal muscle layer, 

 but distinctly in the latter ; it runs into the penis, and opens, 

 as already mentioned, at about the middle of this organ, on to 

 the exterior. 



The ovaries are paired, and lie in Segment 13 ; they are of 

 rather a peculiar form, being narrow, transversely elongate 

 bands ; the ripe ova occupy the unattached margin of the 

 gonads. The oviducts lie in the following segment; the 

 funnel, however, does not open into Segment 13, as is nearly 

 universally the case ; indeed, the only exception hitherto de- 

 scribed is Plutellus. M. Perrier stated ^ that in that genus 

 the oviducts were limited to a single segment; this statement 

 has not, however, met with entire acceptance.^ There is no 

 doubt about the matter in Siphonogaster; it is quite plain 

 in longitudinal sections, which are adapted for proving such a 

 point without leaving much room for doubt. There were, in 

 one example at any rate, two pairs of egg-sacs in Segments 13 

 and 14 respectively ; they are attached to the front wall of 

 those segments. 



I could not find any trace of spermatothecse. But, as is well 

 known, these organs are occasionally wanting in Oligochaeta. 



1 'Arch, de Zool. Exp.,' t. ii. 



2 W. B. Benhara, "Description of Three New Species of Earthworms," 

 ' Proc. Zool. Soc.,' 1892, p. 137- 



