250 



ORDER CYTOLAIMIA 



nema appears to be a typical Monhystera, but careful examination fails to reveal 

 any such well-developed amphids as are characteristic of Monhystera. The 

 spicula are quite different in form from the typical spicula of Monhystera. The 

 intestine also is highly peculiar. Occurs also at Woods Hole, Mass. Fig. 28, p. 249. 



_L 5-_3___-_.._r_8*"_ 'i >m i. .. 



29. Dactylaimus aequalis n. sp. ^6 2.2 2.3 2.5 2. Cuticle naked. 

 Three of the six lips are somewhat more substantial than those alternating with 

 them. Distal thirds of the lips free, the remaining n/ 



portions webbed. From the head, the oesophagus con- 

 tinues to have the same diameter to near the oblique 

 nerve-ring, but then begins to swell gradually so that fh 

 finally it is two-thirds as wide as the base of the neck. 

 There is a small cylindroid cardia. The intestine, 

 separated from the oesophagus by a deep constriction, 



becomes at once about two-thirds as wide as the body. ~^ = ^ f ^- ..^, .. 

 Its circuit appears to comprise about four cells. The ^ 

 lumen of the intestine presents a refractive and distinct contour. From the 

 inconspicuous, slightly depressed anus, the rectum is considerably shorter than 

 the anal body-diameter. The distinct lateral fields are about one-third as wide 

 as the body and contain numerous cells whose nuclei are arranged in two indis- 

 tinct rows along the margins of the field, which they fill fairly well. Renette 

 unknown. The description is derived from a single young female, with the 

 vulva in process of development. The tail is conoid in such fashion that at a 

 distance from the anus about five times as great as the length of the anal body- 

 diameter, where the annules vanish, it has a width about one-sixth as great as 

 at the anus. An indefinite, but probably not considerable portion of the tail 

 of the specimen examined was possibly missing. Hence, the above formula may 

 be only approximately correct. The following formula is in terms of absolute 

 lengths expressed in microns: }]____ ?*____ w_- *?_ ^niojo. 



Habitat: Fine marine mud, San Francisco Bay, California, U. S. A. Sublimate 

 to balsam. Fig. 29. 



1.1 _._ _ Y 72._ 86-' 517 



30. Xenolaimus striatus n. sp. !' *' ~ *' ** * ' " Cuticle naked, 

 and complicated, the annules retrorse posteriorly and the reverse anteriorly. 

 The twelve longitudinal wings extend to near the spinneret, becoming fewer on 

 the tail. The thick, somewhat digitate lips are united by a membrane. The 



M & Set Jb \ set Sllbm portion of the head containing the pharynx is pro- 

 trusile and appears as if surrounded by a balustrade 

 composed of the anterior annules of the cervical 

 cuticle. The large, simple, regular, conoid phar- 

 ynx is fully three-fourths as long as the head is 

 wide. Each of the six lips bears a two-jointed 

 seta, and appears to be armed internally with a 

 slender, flexible element considerably longer than 

 the seta. In the illustration, what appear to rep- 

 resent two minute setae on the foremost annule of 

 the neck are probably the optical expression of an 

 exceedingly tenuous membrane surrounding the 

 head. Although the oesophagus was not plainly seen, it is evident that it is cyl- 

 indroid as in Trachynema. The intestine becomes at once three-fourths as wide 

 as the body. The anus appears continuous. The cells of the intestine con- 



