254 



ORDER CYTOLAIMIA 



mr 



*375 



no granules. From the anus, the posterior lip of which is elevated, the promi- 

 nent rectum leads inward a distance one and one-half times as great as the 

 anal body-diameter. The tail is sub-conoid, at first co- 

 noid, then more or less cylindroid. The elongated caudal 

 glands appear to lie in the anterior half of the tail. 



Habitat: Eel-grass, Woods Hole, Mass., U. S. A. Sub- 

 limate to balsam. Described from a young specimen. 

 Fig. 34a, p. 253; Fig. 346. 



35. Linhomoella exilis n. sp. The shorter cephalic setae 

 are differentiated at the extremity, suggesting that they 

 bear special sensory organs. Cuticle naked except for the 

 setae on or near the head. Lips apparently confluent. 

 Possibly there are papillae immediately around the mouth 

 opening. It sometimes appears as if there is a minute 

 pharynx like that of Monhystera, but this may be a decep- 

 tion due to the structure of the front part of the oesopha- 

 gus; possibly there is no true buccal cavity. Neck cylin- 

 droid. The more or less cylindroid oesophagus is at first 

 three-fifths, near the nerve-ring two-fifths, and finally two- 

 thirds, as wide as the corresponding portion of the neck. 

 tt It is colorless and has a fine musculature. The cylindroid 

 cardia is three-fourths as wide as the neck. The intestine, which is separated 

 from the oesophagus by a collum three-fifths as wide as the base of the neck, 

 becomes at once three-fourths as wide as the body. Near its anterior end, how- 

 ever, there is a broad, shallow constriction, in which region its lumen is faint. 

 Anteriorly the walls are thick, while posteriorly they are thin. A cross-section 

 of the intestine is probably made up of about three cells. These cells contain 

 scattered granules of variable size, the largest of which are about one-twelfth 

 as wide as the body and appear to have the structure of spherical shells. The 

 arcuate tail tapers from the anus to the terminus, where it is one-fourth as wide 

 as at the anus. Caudal , It 



glands were not seen. : ' " ->3-3 



The caudal setae are ' 



very minute and very : 2 - ^ ''- 1 *.^^.*fci 



inconspicuous, five to 



six on each ventrally submedian line. From the con- 

 spicuous, fairly large, elevated vulva the cutinized 



vagina extends one-third the distance across the body. w 



The slender eggs are ten times as long as the body is 

 wide, and appear to be about three-fourths as wide W 

 as the body. The narrow tapering ovaries contain 

 twenty or more ova arranged single file. The proxi- ompu. 

 mal extremities of the stoutish, tapering, acute, 

 rather strong spicula appear to lie ventrad from the x 750 

 body axis, and are not materially cephalated. The 



part of the accessory piece near the spicula is refractive; the apophysis, however, 

 is faint, and a little more than half as long as the anal body-diameter. As to 

 supplementary organs, there are almost invisible ventral innervations, equi- 

 distant and separated from each other by spaces about two-thirds as great as 

 the body-diameter. The ejaculatory duct and vas deferens are about one-third 

 as wide as the body. The tapering testes are very narrow. 



