OXYURIS VERMICULAEIS. 



365 



moutli to within a short distance of tlie tail. The general paren- 

 chyma of the body consists of loose cells lining the central cavity of 

 the body, and some of these appear to be differentiated into special 

 organs of secretion, thus becoming recognized as glands. These 

 glands abound in all parts of the bodies of nematoda, though they 

 are usually most conspicuous towards the anterior part. Some of 



Fig. 79. — Special gland, within the ventral line, immediately in front of the vaginal outlet. 

 {Oxyuris amhigua.) (Considerably enlarged.) — Eberth. 



them attain great size, as I found in the case of a sexually imma- 

 ture round-worm, Ascaris collaris (Linn. Trans., Yol. xxii.. Tab. 32, 

 Fig. 27). 



A great deal of confusion occurs in respect of the water- vascu- 

 lar system and its connection with the glandular elements. Some 

 authors describe, for example, a perforated ventral sucker, which, 



