1 5g(S.S.460) THE M ON ON CHS 



pre-anal ventral row of supplementary organs is essentially the same as in major 

 (fig. 16). According to Steiner's observations the number of supplementary organs 

 in this species may at times be as great as that noted in major. Steiner calls atten- 

 tion to the existence of a submedian row t> pre-anal papillae, lying on either side 

 of the ventral row. The tail bears 3 pairs of papillae, one submedian or subventral 

 pair near the anus ; a second subventral pair slightly behind the middle ; and a third 

 dorsally submedian pair at the beginning of the final fourth of the tail. In the 

 male the slightly conoid spinneret is one-sixth to one-seventh as wide as the base of 

 the arcuate tail. The proportions are about the same as in the female, although the 

 tail of the female is slightly longer and more slender, and not so strongly arcuate. 

 Found among fresh water algae, Cape Van Beneden, Banco Land. It is rather 

 difficult to point out satisfactory differences between this species and major. The 

 pharynx of gerlachei is relatively smaller and is thicker walled, and its dorsal tooth 

 is slightly farther forward. The number of labial papillae sixteen appears to be 

 the same in each. The amphids are perhaps slightly farther back in major than 

 in gerlachei. The number of papillae noted on the tail of the male of major is 

 greater than that noted on the tail of gerlachei, but so far as the distribution of 

 the dorsal papillae on the tail of gerlachei is concerned, they appear to accord very 

 closely with those of major. The two species appear to be closely related. Fig. 26 

 on the previous page (after de Man). 



13. M. fovearum (Dujardin) Bastian. This is an insufficiently known species 

 and may have to be declared nomen nudum. Head a trifle angular. Pharynx 

 angular, "armed with 2 to 3 straight pieces, each ? ? is. ^50' 93. 2 5 , 

 (?) with a pronounced tooth in front of the ? - ? ? 3. ? 

 middle." Tail tapering at first but retaining the same diameter through its pos- 

 terior half, and ending in a sort of spinneret (?). Eggs in single series. 



Found at Rennes, France, in a fresh water ditch, along with Branchipus, ento- 

 mostrica, Eitglena etc. De Man suggests that this species is related to tridentatus. 



14. M. megalairnus, n. sp. Labial papillae obscure. Amphids obscure, half way 

 between the apex of the dorsal tooth and the anterior extremity. Cardia large and 



2.9 9. 28,. 's:?' 38 86. conspicuous, more or 



1 - 8 2 - 6 3- 1 3 - 5 I- 7 ' less cylindroid, three- 



fourths as wide as the body. Intestine about 12 cells in 

 girth, more or less distinctly tessellated. At the end of 

 the anterior third the tail is one-fourth as wide as at 

 the anus. Spinneret slightly swollen, with 2 very small digi- 

 tate setae. 



About the roots of plants, in a tamarack swamp, Wisconsin, 

 \J. S. A. This mononch is peculiar in the relatively meager 

 development of the labial papillae and the pharyngeal teeth, 

 and the weakness of the pharyngeal muscles. Flemming solu- 

 tion to glycerine. Fig. 27. 

 15. M. macrostoma Bastian. Inner set of labial papillae inconspicuous; outer 

 set fairly well developed. The neck tapers but little. The head, however, is rather 

 markedly convex-conoid. De Man describes and figures 2 exceedingly minute 

 submedian teeth at the base of the pharynx. CEsophageal lining strongly devel- 

 oped. Intestine 12 to 15 cells in girth, tessellated. Posterior half or two-thirds of 

 the tail of the female of practically uniform diameter, tapering but very slightly. 

 Spicula arcuate, very slender, about twice as long as the anal body-diameter. Their 

 proximal ends are not cephalated. They are accompanied by 2 accessory pieces, 

 hardly one-third as long, arranged parallel to their distal parts. Supplementary 

 organs, about 20, in the form of innervated papillae, spread over a distance nearly 



