FREE-LIVING NEMATODES 29 



the intestine to one side, is twice as long as the body is wide, one-fourth to one- 

 fifth as wide as long. Just behind the nerve-ring there is a large ampulla as 

 long as the body is wide, and one-third as wide as long. In all the specimens 

 examined there appears a slender seta-like appendage at the mouth of the excre- 

 tory pore somewhat longer than the cuticle is thick. The ovaries are broad. 



The male tail is like that of the female, but more uniformly tapering, with 

 less of a diminution just behind the anus. The strongly arcuate, sub-slender, 

 rather strong and tapering spicula, somewhat cephalated at the tapered distal 

 ends, are one and two-thirds times as long as the anal body-diameter, and lie 

 with their proximae slightly ventral to the body-axis. There are two, more or 

 less separate accessory pieces, each in two parts, one behind the spicula; the 

 other in front or alongside, the front part being like a reduced spiculum. The 

 ejaculatory duct is one-fifth, the vas deferens one-half as wide as the body. 



Habitat; remarks. Cape Royds; Bay. About a dozen somewhat shrunken 

 specimens, the two sexes occurring in about equal numbers. 



LAXUS, Cobb, 1894 



23. Laxus septentrionalis, n. sp. There are upwards of 1000 plain, transverse 

 striae so small as to be difficult of resolution. The three subdistinct, more or 

 less bluntly conoid lips 

 are united by a mem- 

 brane, and form a circlet 

 around the mouth, very 

 difficult to see, except 

 when the mouth is open. 

 Only when the mouth is open can the connecting membrane be seen. It is prob- 

 able that the pharynx contains an obscure dorsal tooth. The structure which 

 gives rise to this supposition is of fair size, and thinly covered w y ith chitin. The 

 cylindroid to conoid neck contains a cylindroid oesophagus, which, measured 

 near the nerve-ring, is one-half as wide as the corresponding portion of the neck. 

 Though the amphids appear circular, they are in reality spiroidal. The pharynx 

 is situated in the midst of an almost imperceptible elongated pharyngeal swell- 

 ing, two-thirds as wide as the head. The thick walled intestine, six cells in girth, 

 soon becomes five-sixths as wide as the body. It has a distinct lumen, and is 

 separated from the oesophagus by a collum hardly one-third as wide as the base 

 of the neck. For a distance about equal to the length of the body-diameter the 

 cells of the intestine are comparatively free from granules. Thereafter they are 

 uniformly packed with yellowish granules having a width a little greater than 

 that of one of the striae of the cuticle. From the continuous anus the prominent, 

 chitinized rectum extends inward and forward a distance three-fourths as great 

 as the length of the anal body-diameter. 



The tail tapers froni the anus to a terminus one-third as wide as its base. Ap- 

 parently the ellipsoidal caudal glands are packed together somewhat behind the 

 middle of the tail. Their ampullae, near the terminus, are more or less distinct. 

 The lateral fields, which are one-third as wide as the body, are margined by re- 

 fractive lines, at least in balsam specimens. The renette has not been clearly 

 seen, but is supposed to be located at a distance behind the neck equal to the 



