258 Mr. R. Daubney on Two Species of 



from just in front of the bursa forwards. The strice of the 

 cuticle are about 3 fi apart. 



The head, which measures about 0'12 mm. in dorso- 

 ventral diameter, has well-developed, freely projecting, 

 submedian papillse, of which that part which is distal to the 

 constriction is elongated rather than spherical. The lateral 

 papillae are small, fairly slender, and do not project through 

 the mouth-collar. The mouth-collar is of medium height, 

 with a rather depressed margin. It is elliptical in outline, 

 and is notched laterally. Tlie buccal capsule itself is ellipsoid, 

 its longer axis directed dorso-ventrally. It is about 0'065 mm. 

 deep. In the dorso-ventral position it appears about as 

 broad as deep, while in the lateral position its width is much 

 greater than its depth. In the latter position its walls in 

 optical section appear roughly triangular, the base being 

 considerably thickened. In the dorso-ventral position, how- 

 ever, this thickening towards the base is much less marked. 

 The internal leaf-crown appears to be absent. The external 

 leaf-crown consists of numerous (upwards of eighty) rather 

 slender elements with rounded tips, which originate from the 

 interior surface of the buccal capsule-wall along the curved 

 line characteristic of the genus. From twenty-six to thirty- 

 two of the elements protrude through the mouth-opening. 

 These projecting leaves, which are mainly confined to the 

 lateral walls, are arranged somewhat in the fashion of the 

 feathers of a fan, the tallest elements being opposite the 

 lateral papillae ; unevenness of length and of origin both 

 assist in bringing about this arrangement. The dorsal 

 gutter is represented by a blunt tubercle on the floor of the 

 buccal capsule. The oesophageal funnel is poorly developed. 

 The oesophagus measures from 0*54 to 0'56 mm. in length 

 and up to 0'16 mm. in maximum thickness. It is bottle- 

 shaped, having a well-defined waist at the point where it is 

 encircled by the nerve-ring. There is a sharp constriction 

 giving rise to a distinct shoulder just behind its anterior 

 extremity. The nerve-ring is situated at about 0*16 mm. 

 from its anterior end, whilst the excretory pore opens just 

 behind its base. 



Female. — The tail of the female is from 1 to 1*1 mm. in 

 length and is sharply pointed. The vulva is situated at about 

 0*7 to 0*8 mm. in front of the anus, or from 1*7 to 1*9 mm. 

 from the posterior extremity. The diameter of the worm 

 increases suddenly immediately in front of the vulva. The 

 vagina is curved spirally and appears to be muscular. The 

 two branches of the uterus run directly forwards to within 



