SUBGENUS MYLONCHULUS 



(S.S.471) 169 



About the roots of banana plants imported from Paris, France. Resembles 

 brachyuris and minor, but differs in having no spinneret. The dorsal onchus is set 

 farther back in the pharynx than in either of those species, and there are no traces 

 of submedian teeth. The rasps also are less strongly developed. Flemming solu- 

 tion to glycerine. Fig. 50 (at bottom of previous page). 



37. M. obliquus, n. sp. Two small, ventrally submedian onchi present, opposite 

 the base of the dorsal onchus. (Esophagus at first a little swollen; its lining well 

 developed, and occupy- 2.6 9. 31. ^63'^ 98. 



ing one-fourth of the 27i 374 374 471 2.4 1>4 M 

 optical longitudinal section. Intestine about 8 cells in girth, 

 as a rule not distinctly tessellated. The conoid tail is slightly 

 arcuate, and obliquely truncate at the spinneret, which is 

 about one-third as wide as the base of the tail. The three 

 caudal glands are located opposite the rectum, which ends 

 externally in a slightly elevated anus. The ampullae of the 

 caudal glands are well developed, and occupy the posterior 

 two-thirds of the tail. Though the vuiva is more or less con- 

 tinuous with the ventral surface, it is conspicuous on account 

 of the refractive nature of the walls of the vagina. The 

 elongated thick-shelled eggs are two and one-half times as long as the body is 

 wide, and appear to be deposited before segmentation begins. The ovaries contain 

 about a dozen developing ova, arranged partly single file, partly irregularly. A pair 

 of ventrally submedian innervated papillae were noted near the middle of the tail of 

 the female. 



From soil from Germany, along with specimens of Heterodera schachtii. Re- 

 sembles brachyuris, from which it seems easily distinguishable by the large thick- 

 shelled eggs. Flemming solution to glycerine. The habitat led to the suspicion that 

 it was feeding on H. schachtii, but the writer was unable to establish the fact from 

 the few specimens available for examination. Fig. 51. 



38. M. lacustris Cobb. The amphids have the form of "slits," 3 to 4 times as 

 long as wide, and are placed at the base of the lips nearly opposite the apex of 



the dorsal onchus. They 2.7 8. 28. *63* 96. /-^p^SscC H* 



are about one-sixth as 275 372 379 472 2.3 ' 



wide as the corresponding portion of the head. Intestine 



from 15 to 20 cells in girth, the cells closely packed with 



granules of variable size in such a manner as to give rise 



to a close and obscure tessellation. The well developed 



lateral fields are one-third as wide as the body. The anus 



is 'slightly raised. The lining of the rectum is distinctly 



refractive. The tail is ventrally arcuate, and ends in a 



blunt spinneret one-fourth as wide as its base, containing 



a well developed, internally ceratinized spinneret. The 



three caudal glands are arranged tandem in the anterior 



half of the tail, the foremost being opposite the rectum. The spinneret appears to 



have a needle-shaped valve. A pair of ventrally submedian innervated papillae has 



been noted a little in front of the spinneret on the female. The eggs, which appear 



to occur one at a time in the uteri, are about one and one-third times as long as the 



body is wide and four-fifths to five-sixths as wide as the body. 



Found in fresh water lakes, Michigan, U. S. A. ; about the roots of ferns, Panama 

 Canal Zone ; and in the Silver Springs, Florida. Resembles M. brachyuris Biitschli, 

 from which it differs in the form of the tail and spinneret. M. polonicus Stefanski 

 seems to closely resemble this species. Sublimate to balsam. Fig. 52. 



