THE ANATOMY OF ONCHOLAIMUS VULGARIS, BAST. 100 



functions, I shall discuss them under the section dealing with 

 this space and its contents, rather than include them in the 

 nervous system, to which they may not belong. 



Yet another type of cell, the coarsely granular acidophil, 

 occurs among the collar-cells as well as elsewhere, but is 

 certainly not nervous. 



The fibrillar groundwork binds together all these various 

 units. 



De Man (12) for the genus Oncholaimus describes 

 numerous cells lying in the body cavity in front of and behind 

 the nerve-ring. 



Bastian (2) also mentions their presence. 



Jagerskiold (10) for Cylicolaimus magnus and Thora- 

 costoma acuticaudatum describes and figures what is 

 evidently an oesophageal collar ; the cells shown in his draw- 

 ings are, however, not so numerous as those in our subject. 

 He frankly states that he has not examined the matter fully, 

 and he does not connect them in any way with the nervous 

 system, but considers them to be the same as the phagocytic 

 " biischelformige organ " described by himself, Nassonow 

 (13), and others in parasitic forms. This opinion, which 

 I believe to be an error, accounts for the fact that he also 

 considers them to be identical with the " floating gland-cells " 

 of Bastian and the " fat cells" of De Man. These cells occur 

 isolated in the " body cavity " through all regions of the body, 

 and are entirely different from this localised compact struc- 

 ture. 



In parasitic Nematodes also a cellular investment to the 

 nerve-ring* is found; e. g. Hamann describes and figui'es it in 

 Lecanocephalus (5) as connected with all four longitudinal 

 lines, and the same holds good for the embryo (A. capsu- 

 laria) which I shall describe later. 



The anal and cloacal ganglia (PI. 7, fig. 6, ag.) are also 

 formed by ingrowths of cells from all four longitudinal lines. 

 Shortly before reaching the level of the anus in the female, 

 or of the cloacal opening in the male, cells begin to project 

 inwards from the dorsal and the two lateral lines, passing 



