464 ARABIAN NEMATODES, 



and are placed behind the pharynx at a distance from it equal to 

 the width of the head. The whole middle thii-d of the oesophagus 

 is of uniform diameter, being less than half as wide as the neck ; in 

 the anterior third it expands very gradually to the pharynx ; in 

 the posterior third it expands rapidly in diameter, becoming 

 widest (two-thirds as wide as the neck) in the seventh eighth, 

 and diminishing thence to the distinct cardiac collum. A three- 

 lipped cardia projects into the distinct but small cardiac cavity. 

 The intestine is two-thirds as wide as the body. The narrow 

 rectum is a trifle longer than the anal diameter. The nerve-ring, 

 making an angle of QO^ with the axis of the body, is wider than 

 the oesophagus at the point encircled. Nerve-cells are abundant 

 on both sides of the nerve-ring. I saw no venti'al gland. The 

 tail is conoid or convex-conoid from the inconspicuous anus, and 

 contains three unicellular caudal glands placed in a longitudinal 

 row behind the anus. Of these glands the posterior is the 

 smallest : all empty as usual at the terminus. A vagina shorter 

 than the diameter of the body leads forward from the incon- 

 spicuous vulva into the single uterus, which contains three or four 

 ellipsoidal eggs one and one-half times as long as the body is wide, 

 and half as wide as long. From the uterus the straight ovary 

 extends forward to near the cardiac collum. 



■6 9-2 19'2 -M 87-2 



1-4 19 2-2 2-2 2- ^'^^ ™™- Tail of tlio male like that of the female. 

 Tiie two equal, linear, uniformly arcuate spicula are of nearly the 

 same size throughout, and are twisted so that when exserted they 

 project to the right and left, or even in a posterior direction. 

 Their proximse are small and cephalated by constriction. Accessory 

 pieces two, joined, exserted with the spicula, at least when the 

 animal is killed with chemicals. The ductus ejaculatorius is 

 longer than the oesophagus ; from it the straight testicle extends 

 forward and ends just behind the cardiac region. The species is 

 characterised by the ventral row of six to seven very small equi- 

 distant papillse, which exists on the male in front of the anus. 

 The hindermost of these papillae is opposite the proximal ends of 

 the spicula, and the foremost is about as far from the anus as is 



