778 CONTRIBUTION TO AUSTRALASIAN OLIGOCHiETA, I., 



canal. The wall of the spermiducal gland consists of large 

 truncately cuneate cells, with granular cytoplasm, each with a 

 large spherical nucleus situated in its outer portion. No traces 

 of musculature investing these glandular cells can be detected. 

 The sections through this gland constitute the most prominent 

 structures to be seen in sections through this region with the 

 exception of the ovary. The penis consists of a pyriform body 

 enclosed in a penial sac, which is continuous with the organ 

 itself on the dorsal aspect in the region where the atrial canal 

 passes into the penial canal. The cavity of the penial sac is 

 pear-shaped, its neck-like portion opening on the exterior in 

 segment xii., immediately behind the anterior septum of that 

 segment. The sac is lined by a flat epithelium with spherical 

 nuclei, and this is invested by circular muscle-fibres external to 

 which is a peritoneal epithelium. 



The wall of the penis itself is differentiated into three portions. 



(1) An internal epithelium surrounding the very minute lumen. 

 The cells of this layer much resemble those of the spermiducal 

 glands, but are much smaller. They are squarish in shape, with 

 spherical nuclei, and non-ciliated. They secrete externally a 

 cuticular substance which stands out distinctly as a bright, 

 highly refractive band investing the epithelium. 



(2) A spongy mass consisting of a matrix in which are scattered 

 muscle-fibres circularly or obliquely arranged, and external to 

 this again isolated strands of longitudinal fibres. 



(3) Columnar epithelial cells with centrally placed spherical 

 nuclei. 



Although the penis was not found protruded in any specimens, 

 one may safely say, I think, that it can be. 



In PI. xxix, tig .4, is shown the male efferent apparatus recon- 

 structed from longitudinal sections. 



In examining an entire specimen, one notices two large sper- 

 mathecal chambers, circular in optical section, lying in segment 

 xiv., one dorsal to, and slightly overlapping the other. In 

 longitudinal sections it is seen that the ventral chamber is con- 

 nected with the ventral body-wall, as stated previously, by a 





