ACTINONEMA, RHIPS 339 



pharynx is very small and inconspicuous, or even absent apparently. There seems 

 to exist, however, a minute, more or less arcuate dorsal onchium, to be seen in 

 balsam specimens only when -exserted. The neck is conoid, the head convex- 

 conoid. Amphids nearly straight transverse slits, four-fifths as long as the 

 corresponding diameter of the head, and apparently eight times as long as wide. 

 One of the foremost annules appears to be more or less dislocated; that is to 

 say, the regular succession of the fore-most annules is somewhat disturbed by 

 X?50 \>\ SP ^ ne P resence f the amphids, which are otherwise almost 



invisible. Oesophagus more or less conoid, but decidedly 

 clavate posteriorly. Near the head it is two-fifths, near 

 the nerve-ring about one-fourth, and finally one-half, as 

 wide as the corresponding portion of the neck. There is 

 no distinct cardia. The rather thin-walled intestine, which 

 becomes at once two-fifths as wide as the body, has a dis- 

 tinct lumen. Its cross-section presents four to six cells. 

 Cardiac collum one-fifth as wide as the body. From the 

 depressed anus the prominent cutinized rectum is one and 

 one-fourth times as long as the anal body-diameter. The 

 cells of the intestine contain numerous, very fine, colorless granules. The co- 

 noid, subarcuate tail tapers from in front of the anus to the simple, unarmed, con- 

 vex-conoid, rather blunt spinneret. The ellipsoidal caudal glands are small 

 and inconspicuous, more or less unsymmetrical, and apparently lie in a close tan- 

 dem opposite the anus. The elongated to fusiform, granular renette cell lies 

 behind the neck a distance equal to one and one-half body-diameters; it is as 

 long as the body is wide and one-fifth as wide as long. Female sexual organs 

 double. The tapering ovaries are of moderate size and extend half way back to 

 the vulva. They contain few ova arranged for the most part single file. The 

 simple, strong, tapering, rather stout spicula are at their widest part about one- 

 sixth as wide as long. Their proximal ends appear to lie more or less opposite 

 the body-axis. The simple, rather frail, slender accessory piece is about two- 

 thirds as long as the spicula. There are no supplements or special papillae. 

 Habitat: "Seagrass," shoal, two miles off Key West, Florida, U. S. A. Fig. 117. 



118. Rhips ornata n. sp. 1.3 i.i/~ 2~._6. 3- 1.9 ' " Cuticle thick, contour 

 more or less crenate. Striae resolvable into rod-like markings, ygf//n/ ._ ppl(l)l 

 changing so as to produce a basketwork-like effect on the neck. 

 On the posterior half of the body on each lateral field each 

 annule presents two forward-pointing, "V "-shaped marks of 

 unequal size, the ventral being the larger; these are inconspicu- 

 ous, but are less so posteriorly. These markings occur also on 

 the anterior half of the body, but are there reversed. On a par 

 with the celphalic setae, and just in front of the ends of the 

 amphids, there are four sublateral, special scales, or short, 

 more or less conical horns, about half as long as the setae, (ppl Fig. 118a.)- 

 What function is associated with these peculiar appendages is unknown. Lips 

 very minute, apparently six and double. The neck has the peculiarity of dimin- 

 ishing more rapidly from the middle forward for a short distance. The dorsal 

 onchium is opposed by one or two very minute ventrally submedian ones. The 

 oesophagus is conoid, though there is a more or less pronounced clavate cardiac 

 swelling. At the nerve-ring, the oesophagus is one-half, and finally three-fourths, 



