130 F. H. STEWART. 



by Jagerskiold. I have not detected any opening through 

 the shell, but such an opening would no doubt be very minute, 

 and it is difficult to obtain a complete series of sections of the 

 ova without some slight tearing of the tough shell. 



The vulvar aperture is slit-like, the greatest diameter trans- 

 verse to the long axis of the body. 



The gonenteric canal. — This is a minute duct which, 

 as stated above, opens into the vagiua close to its com- 

 mencement (PL 8, fig. 23, gee.)— in fact, just below the 

 sphincter at the junction of uterus and vagina. It traverses 

 the dorsal wall, passing vertically through the muscular 

 layer. In this part of its course a few minute nuclei indi- 

 cate the presence of an exceedingly fine lining of epithelial 

 nature. Emerging from the vaginal wall, it lies in the body- 

 space (PI. 8, fig. 22, gee.) with nucleated protoplasmic walls 

 Avhicli conduct the canal to the gut in the raidventral line 

 (PI. 8, fig. 21, gee.) and becomes continuous with the ali- 

 mentary epithelium. Passing from the vagiua to the gut, 

 the canal inclines slightly away from the mid-point of the 

 body — i.e. the anterior canal inclines slightly towards the 

 head, the posterior slightly towards the tail. 



The function of this canal is to carry off superfluous sper- 

 matozoa. Spermatozoa are found in it and one of my sections 

 shows a sperm passing from it into the gut. The gut in the 

 adult female contains large masses of sperms. 



No such canal has been described previously in any nema- 

 tode. Its comparative morphology will be discussed later. 



Reproductive Organs in the Immature Female. 



I was fortunate enough to secure a specimen which was 

 full grown, but in which the reproductive organs were unde- 

 veloped. In this specimen the gonads occur in from one fifth 

 to one fourth of the length of tlie body. The vulva lies some- 

 what behind the centre. 



They consist, as in the adult, of two tubes, an interior 



