Sept. 15, 191S 



Tylenchus Similis 



565 



of the larger sort, are of very much larger size and give to the organ its 

 peculiar pearly appearance. 



From the inconspicuous anus the rectum leads inward and for\vard a 

 distance about equal to the anal body diameter. The tail is conoid to 

 the rather blunt roughly conoid terminus, 

 which has a diameter about one-third ot 

 one-fourth as great as that of the base of 

 the tail. On each lateral line, a little in 

 front of the beginning of the middle third 

 of the tail, there is a minute pore, which 

 is possibly homologous with the single 

 papilla found in the corresponding posi- 

 tion on the tail of the male. The final 

 striae are rather indefinite, so that the 

 terminus appears almost as if not striated. 

 The lateral fields appear to be more than 

 one-third as wide as the body. The ex- 

 cretory pore is rather conspicuous, as is 

 the duct leading to it. Both walls of the 

 duct are distinctly refractive, and its lumen 

 may readily be seen. The pore is located 

 about as far behind the median bulb as the 

 base of the spear is in front of it. The duct 

 leads backward a distance equal to three to 

 four body widths, and there joins the rather 

 small ellipsoidal renette cell located on the 

 left-hand side of the body. The exact 

 details of this renette cell are not yet clear. 

 There is a conspicuous refractive cell of 

 rather uniform granular texture located 

 just behin^ the excretory pore. This cell 

 is longer than the body is wide, about one- 

 third as wide as long, and has a strongly 

 refractive nucleus about one-fourth as wide 

 as itself. Closely associated with this cell 

 are two others of similar form but some- 

 what smaller, the three forming a close 

 tandem series twice as long as the body is 

 wide. As a rule, the two posterior cells of 

 this series exhibit peculiarities not shown 

 by the anterior cell ; they do not stain so 

 strongly with carmine, and in general are 

 less conspicuous. These three glandular cells empty through a narrow 

 duct which enters the base of the oesophagus in the rear of the nerve 

 ring, passes through the median bulb, being diverted to pass around the 

 central valve on its dorsal side, and extends thence onward to near the 



Fig. I. — Tylenchus similis: Nearly adult 

 female, a. Lip region; b, spear guide; 

 c, 3-bulbed base of spear; d, ampulla, 

 salivary gland; e, oesophageal lumen; 

 /, oesophagus; g, median bulb; h, nerve 

 cells; J, nerve ring; j, excretory pore; 

 k, initial intestinal cells; /, anterior sali- 

 vary gland; TO, m, end of ovary; M.ovum; 

 o, renette duct; p, posterior salivary 

 gland; g, fat grantile, intestine; r, re- 

 nettecell (?); j, terminus; /, caudal pore; 

 u, vulva; v, anus; iv, crenate •cuticle; 

 X, X, spermatozoa. 



