BY N. A. COBB. 463 



remaining one, the left submedian. The two circular lateral organs 

 are situsted opposite the lower part of the pharynx, which they 

 equal in width. No eye spots exist, but an abundance of brown 

 pigment is found in the head and neck. The pharynx, two-thirds as 

 wide as deep, bears three teeth — one, the left submedian, reaching 

 nearly to the lips, the remaining two being only half as long. 

 The oesophagus is swollen to receive the pharynx, then diminishes 

 and becomes uniformly about one third as wide as the neck, until 

 gradually swelling in the posterior fourth to more than twice 

 that width. Cardiac collam distinct. Intestine two-thirds as 

 wide as the body. The ventral gland, lying somewhat behind 

 the cardiac region, empties, — by means of a long and very narrow 

 duct and small ellipsoidal ampulla, — through a porus excretorius 

 situated twice as far behind the base of the pharynx as the latter 

 is behind the lips. The ventrally ai'cuate tail is conoid, but 

 tapers more rapidly in the anterior than in the posterior half. It 

 bears a number of hairs. Terminus somewhat swollen, its 

 diameter one-fourth as great as the anal diameter. Tail glands 

 present. The two equal, linear, nearly straight spicula scarcely 

 exceed the anal diameter in length. Seen in profile, they seem to 

 lie at an angle of 45° with the axis of the body. Their proximse 

 are scarcely enlarged. Four pairs of bristle-bearing submedian 

 papillae stand opposite the spicula. The anterior third of the tail 

 is armed with three similar pairs. The two equal testicles occupy 

 the middle third of the body. 



Hah. — Beach sand ; Aden, Arabia. Mature in February. 

 MoNHYSTERA, Bastian. 



T* T *6 8'7 W'2 -64 '8 89' 



M. MAS-PAPILLATUS, n.Sp. fiT' l-Q 22 ao 17 l"59mm. Cuticula 



finely striated. To the convex-conoid neck succeeds, somewhat in 



front of the two circular lateral organs, a distinctly expanded head, 



which is rounded in front, and bears six long setae but no papillae. 



These setae are situated opposite the middle of the unarmed, 



gaping, cyathiform pharynx, two of them being lateral and four 



submedian. The lateral organs are one-third as wide as the head, 

 32 



