BY N. A COBB. 



393 



organs are symmetrical. Like the Enopli, these worms are 

 carnivorous. 



_^ 1-5 7-4 1 4- '50^ 



D. RAPAX, n.Sp. 2-2 ■ 2-7 



22 



94- 



1-25-2 mm. The rather thin 



4-4 2-6 



cuticle bears papilla-like hairs throughout and is traversed by 

 about one thousand transverse strise, 2-2jli apart, and composed of 

 dots also about 2/i apart. The neck tapers but little ; the head is 

 rounded. The spiral lateral organs are one-third as wide as the 

 head and are situated opposite the middle of the pharynx ; the 

 the left hand organ is a right-handed spiral, and the right hand 

 one, of course, a left- 

 handed spiral. The six 

 very short cephalic setse 

 are seen with difficulty ; 

 two are lateral and four 

 are submedian. A second 

 row of four C?) submedian 

 setse occurs immediately 

 behind the lateral organs. 

 When the lips are closed 

 the pharynx appears as 

 a central chitinous line 

 accompanied by three 

 apophyses, one of which 

 is ventral and two of 

 which are dorsally sub- 

 median. The three "apo- 

 physes " are the optical 

 expression of three deep 



folds in the closed pharynx. When the mouth is opened to 

 seize the prey, the three parts of the pharynx corresponding 

 to the three lips spring outward, being moved by powerful 

 muscles. The mouth closes after the manner of a chuck, and 

 the prey is held firmly by means of numerous large horny teeth 

 on the inside of the anterior part of each jaw. The oesophagus 

 is phalangiform and muscular ; in the narrowest part it is half 



Fig. b.—Demonema rapax. 



I, female. II, head of 

 same III, tail, spirally 

 wound, showing its use as a 

 prehensile organ. IV, ter- 

 minus, showing the elongated 

 outlet for the caudal glands. 



a, lips. 



b, cephalic setse. 



c, lateral organ. 



d, ventral apophysis. 



e, nerve-ring. 



/, ampulla of duct of ventral 

 gland. 



g, (?). 



h, ventral gland (black). 



i, intestine. 



j, terminus. 



k, bend in ovary. 



I, uterus. 



m, egg. 



n, vulva. 



0, cells of intestine. 



p, swelling at terminus. 



q, slender terminus. 



r, anus. 



s, three caudal glands. 



