1914-] F- H. Stewart t Free-Living Nematodes. 251 



in front of the lateral organs. Intestine with brown granules and 

 without tesselation. 



Neither nerve ring nor cellular collar visible. 



No ventral gland. 



Fundus of ovary 0*205 mm from head. Gonad tube single 

 as in the genus. Uterus contains large unsegmented ova. 



Male. — General outline resembles the female but the tail is 

 more blunt. (PI. xxxii, fig. 25). 



The specimen is coiled on itself, and owing to its delicate 

 character could not be straightened. The head is therefore seen 

 obliquely and foreshortened. Indications of a buccal cavity are 

 however visible, together with the cephalic ring of setae as in the 

 female (PI. xxxii, fig. 26). Lateral organ faintly distinguishable. 



Cuticle as in the female. No bristles observed on the body. 



Tail narrows abruptly near the termination. No glands, 

 papillae, or bristles. 



The testis commences immediately behind the oesophagus 

 and lies on the left side of the intestine. Vas deferens situated 

 ventrally to the intestine. Spicules (PI. xxxii, fig. 27) with knob- 

 like proximal extremities, twisted shafts, and glans-like distal 

 extremities, hollow. 



This species resembles M. dubia, Biitschli, and M . agilis de Man, 

 in possessing a transversely striated cuticle ; contrasted with the 

 former, however, it is of more slender form, and the lateral organs 

 are not spiral ; contrasted with the latter, the vulva is situated 

 more posteriorly, and the distance from vulva to anus is equal to, 

 not twice as great as, the distance from anus to tail. 



^ X — X — 2-6g— 2-84— 2 



Cobb's Formula, 



0-69— X — i6-i — 78"i — 88" 



LIST OF SOME IMPORTANT PAPERS DEALING WITH 

 FREE-LIVING NEMATODES. 



(i) Bastian, Charlton Monograph of the Anguilluhdae.— 



Trans. Linn. Soc, vol. 25, 1866. 



(2) Biitschli, O. .. Beitrage zur kenntniss der freilebenden 



nematoden. — Nov. Ad. Kais. Leop. 

 CaroL A had. 



(3) Biitschli, O. .. Zur Kenntniss der freileb. Nemat.— 



Senckenbg Natforsch. Ges. Abhand. 



(4) Daday, V. .. Freshwater nematodes of South 



America. — Zoologica, 1905, p. S^- 



(5) Daday, y. .. Freshwater nematodes of German 



Africa. — Zoologica, 1910. vol. 23. 



(6) Daday, V. .. Die freilebende Siisswasser-Nematoden 



Ungarns. —Zoologisch. J ahrb. . Syst., 

 Bd. 10. 



(7) ]\Ian, de .. Nematoden der Niederldndisch. Fauna, 



Leiden, 1884. 



