XENOLAIMUS, CYTOLAIMIUM 



251 



tain scattered granules of variable size, the largest of which are one-half as wide 

 as one of the annules. The conoid tail tapers from in front of the anus and 

 ends in a spinneret. 



Habitat: Marine mud from near the government-dredged cut, Biscayne Bay, 

 Florida, U. S. A. Sublimate to balsam. Fig. 30, p. 250. 



31. Cytolaimium exile n. sp. Cuticle thin, without setae except those on the 

 head. Lips with thin distal flaps as in Monhystera. The cylindroid oesophagus 

 is at first three-fifths, near the nerve-ring one-half, and finally three-fifths, as 

 wide as the corresponding portion of the neck. There is a conoid cardia one- 

 third as wide as the base of the neck. The thick-walled intestine, which has a 

 faint lumen, becomes at once three-fourths as wide as the body. Its cells contain 

 scattered granules of variable size, the largest of which, near the neck, are one- 

 fifteenth as wide as the corresponding portion of the body, but near the middle 

 of the nema are one-tenth as wide as the body. The conoid tail tapers rather 

 regularly from somewhat in front of the anus, but faster near the anus. No 

 clear evidence of the presence of caudal glands. The lateral fields are about 

 one-half as wide as the body. The narrow nerve-ring is accompanied by obscure 

 nerve cells. From the small, continuous, inconspicuous vulva, a small, more or 

 less weak, non-cutinized vagina extends inward one-third the distance across the 

 body. In the narrow, tapering ovaries, the ova are arranged single file. Only 

 one egg at a time occurs in each uterus. The eggs are three times as long as the 

 body is wide and appear about three-fourths as wide as the body. The tail of 

 the male is first conoid, then cylindroid in the posterior two-fifths, where it is 

 one-third as wide as at the base. The somewhat stout, rather blunt spicula are 

 strong, non-cephalated, and so situated that their proximal ends appear to lie 



: --...-V- '-57-' n. ( , opposite the 

 ^*.i body-axis. Ihere 



T M w * 95.5 . is u a "fractive 

 -.- *" ...^....3.5.. short element in 



front of the tips 



fUbfh of the spicula. Accessory piece slender, appar- 

 ently strong, one-third as long as the spicula. 

 The 16 pairs of submedian, equidistant, discoid, 

 slightly-elevated supplements are not cup- 

 pli shaped, and are relatively less cutinized than 

 in well-developed Chromadora supplements. 

 The posterior pre-anal pair lies opposite the 

 distal parts of the spicula. Thence, forward, 

 X 750 placed at intervals about equal to three-fourths 

 the body-diameter, the organs occupy a space 

 eight to nine times as long as the anal body-diameter. The post-anal five pairs 

 occupy the anterior three-fifths of the tail. The discs are about one-fourth as 

 wide as the body, and one-fourth as wide as high, the distance between them being 

 about one and one-half times their diameter. There appears to be an innervated 

 element that projects from near the center of each disc. The ejaculatory duct, 

 which is co-extensive with the pre-anal supplementary organs, is one-half as wide 

 as the corresponding portion of the body. The vas deferens is one-half to one- 

 third as wide as the body. Each testis is at first about one-third as wide as the 

 body and cylindroid, but afterwards tapers. The anterior testis is much the 

 longer. 



Habitat: Sand-bar opposite Miami River, Biscayne Bay, Fla., U. S. A. Sub- 

 limate to balsam. Fig. 31. 



lit (3) 



