768 anticoma: a genus of free-living marine nematodes, 



herbivorous. Now and then diatoms are seen in the alimeatary 

 canal. 



Key. 



Poius near the nerve-ring 1. typica. 



Porus about half way between the nerve-ring and 



head 2. Eherthi. 



Porus near tlie head. 



Pectoral hairs lateral only, few (five) 3 acuminata. 



Pectoral hairs median (?) and submedian, 



numerous 4. leptura. 



•0 10-5 20-3 '48'^* 86-5 



1. A. tyjnca, n.sp. 



1-3? mm. This is a homo- 



's 2- 2-5 3-2 1-8 



cephalous species which may almost be said to be devoid of a 

 pharynx. Tlie neck is slightly convex-conoid, 

 especially in front of the pectoral hairs, which 

 occur in two opposite lateral sets of four each 

 at one-fourth the distance from the mouth to the 

 nerve-ring. The cephalic setae stand out half 

 way between the anterior extremity and the 

 lateral organs, the latter being a little in front 

 of half way between the anterior extremity and 

 the pectoral hairs. All these particulars ai-e 

 shown in the upper right figure in the adjacent 

 illustration. The oesophagus is about one-third 

 as wide as the neck, except in the posterior third 

 where it gradually becomes one-half as wide as 

 the neck. The tessellated intestine becomes at 

 once two-thirds to three-fourths as wide as the 

 body and is found to be composed of cells of 

 which about fifteen side by side make up the 

 circumference. The ellipsoidal or oblong uni- 

 cellular ventral gland (as long as the body is 

 wide^ is situated just in front of the cardiac 

 collum, and presents the peculiarity of being 

 i^eflexed and extending forward from the point of juncture with its 

 duct. This latter meanders with somewhat irregular width to the 



Fig. 1. Anticoma typica- 



