336 ORDER ANAXONCHIA 



Its proximal half curves away from the spicula and then recurves, and is con- 

 nected with the ventral part of the body-wall a short distance behind the anus 

 by means of oblique muscles. 



Habitat: Coral sand, New Hebrides. This genus differs from Chromadora, 

 Spilophora and Euchromadora in the possession of distinct circular amphids, 

 and also in the possession of twelve longitudinal cuticular costae. In this latter 

 respect it resembles Monoposthia, but here the spicula are double, and there 

 are no supplementary organs or swellings. The lip-region and pharynx also pre- 

 sent contrasts with any of the above genera. The striking differences are: (1) 

 The continuation of the pharynx in its narrow part as a definite well lined pos- 

 terior chamber, ending definitely opposite the point where the pharyngeal bulb 

 is separated from the oesophagus by a distinct constriction. (2) By the form of 

 the lips, which, instead of being soft and internally folded so as to give rise to 

 about twelve refractive ribs, or folds, are more strongly built, cutinized and out- 

 wardly recurved, and are only six in number. (3) -M-Fig. 114, p. 335. 



A-.5. . . 9.7 .;. i6 : 6 ...'*-* aq. . 4> 4 _ 



115. lotadorus punctulatus n. sp.mj* 5-* : 5J 6.5 "* 5.9 ' Striae of the 

 naked cuticle resolvable into rows of dots, which are modified a little on the 

 lateral fields, where there are distinguishable two longitudinal rows of markings 

 close together on each side of the lateral line, at least toward the anterior extrem- 

 ity and on the neck. The neck is cylindroid. There are probably four or six 

 short and inconspicuous cephalic setae in the midst of the labial constriction. 

 There are twelve lips of the character usually found in the genus Cyatholaimus, 

 but smaller, and in such a position in the specimen examined that it is impos- 

 sible to make out the details, except that when the mouth is open about twelve 

 papilla-like lips of small size are to be seen toward the margin of the head. 

 Behind the pharyngeal bulb the oesophagus is about one-half as wide as the 

 base of the head. It continues to have this diameter until after it passes through 

 Ub _ M Hi the nerve-ring, when it expands to form the pyriform cardiac 



bulb, which contains a distinct but simple valvular apparatus. 



The intestine joins the middle of the posterior surface of the 



3~~fjgK3r / cardiac bulb, and is at that point only about one-fourth as wide 

 g|l Qg as the base of the neck; it gradually widens out so as to become 

 half as wide as the body. It would present few cells in cross- 

 750 section, perhaps only two. The renette cell is about one-third 

 as wide as the body, and fully twice as long as wide, and lies a short distance 

 behind the base of the neck. The tail of the male is conoid in the anterior three- 

 fourths; thence onward it tapers more rapidly to the minute spinneret. The 

 posterior fourth of the tail is more finely striated than the remainder. Caudal 

 setae few, minute, and scattered. The proximal ends of the uniform spicula are 

 bent over toward the ventral side of the body. The spicula are of very peculiar 

 form, the proximal halves being much more strongly arcuate than the distal 

 halves. At the distal extremity each spiculum is bifurcated, one fork, the 

 anterior, being rudimentary, while the other, the posterior, is somewhat S-shaped 

 and acute distally. The finger-shaped apophysis of the accessory extends back- 

 ward nearly parallel to the body-axis. The apophysis is nearly as strongly cutin- 

 ized as the spicula themselves, and has a length nearly equal to that of the anal 

 body-diameter. The apophysis is nearly twice as wide as the spicula, which 

 have a width about equal to that of three of the adjacent annules of the cuticle. 

 Ejaculatory duct about one-third as wide as the body; vas deferens about half. 

 Habitat: Punta Arenas, Pacific coast of Costa Rica. Marine. Fig. 115. 



