78 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 50. 



cylindrical esophagus is followed by a bulb ap- 

 proximately as long as the esophagus and contain- 

 ing a triangular tooth apparatus. The excretory 

 canals begin at the level of the esophagus in a 

 large, strongh^ granular cell containing a vacuole. 

 The cuticle has a fine transverse striation which 

 disappears behind the anus. 



Male unknown. 



Female 25 mm. long. Esophagus, including 

 esophageal bulb, 700 [>. long. Originating in a 

 large cell at the level of the middle of the esopha- 

 gus, the excretory vessels extend through the lateral 

 fields, which consist of two lateral cells and one 

 median projecting cell perforated by the vessel. 

 Just in front of the vulva the anterior and posterior 

 half of each canal unite to form a reservoir which 

 opens externally through a fine aperture. The 

 cylindrical intestine lies mostly along, the right 

 lateral line and is compressed posteriorly. It 

 terminates in a short rectum having a quadrangular 

 cross section. The rectum is joined to the body 

 wall by four membranes and shows large rectal 

 cells on its anterior boundary. The anus is 7 mm. 

 from the end of the tail. The ovaries (fig. 90) 

 originate in the anterior portion of the body and 

 increase in diameter with, egg production. At their 

 transition into the oviducts they narrow abruptly. 

 Just in front of the anus, the oviducts enter the 

 large uterus, which passes to the anterior portion 

 of the body and tui-ns back as the vagina, which is 

 short and surrounded by circular muscles. The 

 muscles are not present at the vulva, which is a 

 broad cleft with swollen edges situated 4 mm. from 

 the head (fig. 91). The eggs are apparently of 

 typical Oxyurls form, flattened on one side. 



Host. — Procaoia syrlaca {Iliji'dJ' si/riacus). 



Location. — Cecum. 



Locality. — Near Mount Sinai, Palestine. 



Hemprich and Ehrenberg descril)e two varieties 

 of this species as follows: 1. Variety ohtusa; yel- 

 lowish, the curved tail more than a third of the 

 body length, neither pointed nor alate. 2. Variety 

 acuta; white, the straight tail not exceeding a third 

 of the body length, pointed but not alate. It seems 

 possible that these writers were dealing with two 



Fig. 90.— OxYxmis 

 flagellum. fe- 

 male genitalia. 

 Enlarged. 

 After Nasso- 

 Nov, 1897. 



