282 



PARASITES OF THE DOMESTIC ANIMALS 



Fig. 145. — CEsophagostomum columbianum ; male 

 at left, female at right. * Vulva. x5. (After Ran- 

 som, Bull. No. 127, Bureau An. Ind., U. S. Dept. 

 Agr.). 



^— —int 



The eggs are oval, 65-75 microns in Fig- 146.— CEsophagostomum col- 



length by 40^5 microns in breadth. "^^^T^^^^^^t^. 

 Segmentation occurs while they are within ncai groove; c. p., cervical papilla; 



the uterus ^^■' esophagus; int., intestine; 1. m., 



ml J. 1 1 nnr\ ■ lateral membrane; 1. p., lateral cir- 



The freed embryos measure 230 mi- cumoral papilla; m.c, mouth collar; 



Crons in length. n. r., nerve ring. (After Ransom, 



Parasitic in the large intestine of the ?""■ -^°; \27. Bureau An. ind., 



, , , = U. S. Dept. Agr.). 



sheep and goat. 



2. CEsophagostomum venulosum. Fig. 148. Strongylinse (p. 280). 

 — The thickness of the body is nearly uniform over its greater portion, 

 attenuated toward ends. The anterior end is usually straight. The 

 height of the cuticular collar about the mouth is about one-third of its 

 diameter. The cuticle of the neck is inflated between the mouth collar 

 and the cervical groove. The lateral membranes extend well back but 

 are very narrow. The bursa of the male has two lateral lobes united by a 

 small median lobe. The spicules are 1.1-1.5 mm. long. The vulva of 

 the female is naked and located just in front of the anus. From a short 

 distance in front of the vulva the body tapers, terminating in a sharply 

 pointed tip. 



The female is 18-24 mm. (23/32-15/16 of an inch) in length; male, 

 12-16 mm. (15/32-5/8 of an inch). 



The eggs are oval, 90 microns in length by 55 microns in breadth. 



