LAIMELLA, ILLIUM 



261 



1.3 5-4 9.2 "-3?-". . .70.. . 1 



44. Laimella longicauda n. sp Li" 'i.j/ ' to ..... i* 1-7 ' " Striae difficult to 

 detect, but resolvable into almost invisible dots. Cuticle naked. Labial papil- 

 lae obscure. Pharynx closed, inconspicuous, but undoubtedly present. There 

 is a slight thickening or extra-refractiveness at one portion of the pharyngeal 

 wall that suggests the presence of an extremely minute onchium. The cylindroid 

 oesophagus near the nerve-ring is two-fifths as wide as the neck, and ends in an 

 ellipsoidal valveless bulb three-fourths as wide as the base of the neck. The 

 oesophagus has a fine colorless musculature. Hemispherical cardia, two-sevenths 

 as wide as the base of the neck. The thick-walled intes- 

 tine, set off by a cardiac collum one-fifth as wide as the 

 neck, becomes gradually five-sixths as wide as the body, 

 its cross-section presenting about six cells. From the 

 somewhat depressed anus, the rather prominent cutin- 

 ized rectum extends inward a distance equal to the anal 

 body-diameter. The colorless, scattered to numerous 

 intestinal granules are of variable size, the largest of 

 them at first only twice as wide as one of the annules, but 

 near the middle of the body six to eight times as wide. 

 Tail setaceous, but conoid for a distance six times as 

 great as the anal body-diameter, at which distance it is one-fifth as wide as at 

 the base; thence it tapers very gradually to the terminus. It is very doubtful 

 if there is a spinneret. There are elements in the base of the tail, simulating 

 caudal glands, but no definite ducts have been seen, and the terminus seems 

 too fine to afford space for a spinneret. About six very slender caudal setae, 

 each about two-thirds as long as the anal body-diameter, occur on each of the 

 four submedian lines. Similar setae occur throughout the body. The lateral 

 fields are two-fifths as wide as the body. The large, non-granular, elongated 

 renette cell lies just behind the base of the neck, and empties through an ellip- 

 soidal ampulla, one-third as wide as the neck. The broad, oblique nerve-ring 

 is accompanied by rather obscure nerve cells. From the small, more or less 

 continuous vulva, the moderate-sized, conoid, cutinized vagina extends three- 

 fifths the distance across the body. The elongated eggs are one to one and one- 

 half times as long as the body is wide. The ellipsoidal sperm cells in the uterus 

 are granular and about half as long as the body is wide. The cylindroid ovaries 

 contain at least ten ova, arranged single file. 



Habitat: Algae, Key West; also mud-flat, Biscayne Bay, Florida, U. S. A. 

 Flemming to glycerine jelly. Fig. 44. Terminus, trm, shown foreshortened. 



* 750 



45. Illium exile n. sp. - 4 -^ i- 1-1 .e >2 ' 5 " Cuticle naked. Neck co- 

 noid. Oesophagus conoid, finally about three-fourths as wide as the base of the 

 neck. Cardia elongated, half as wide as the base of the neck. The intestine 

 amoh \arna becomes at once about two-thirds to three-fourths as 

 I \ wide as the body. Its cross-section appears to be 





\j/spn made up of about six cells. The posterior lip of the 

 anus is slightly elevated. From it there extends 

 inward the rather strongly cutinized rectum, which 



is about as long as the anal body-diameter. The lateral fields are a little more 

 than one-third as wide as the body. The ventral gland is a much elongated 

 cell, lying at a distance behind the base of the neck equal to about three to four 

 body-diameters, and having a width about one-fourth as great as that of the 

 corresponding portion of the body. There is a distinct ellipsoidal ampulla 



