STRONGYLINiE 291 



the intestine where they attach and are sexually mature, the sexes often 

 being found coupled in this location. Before their intranodular existence 

 the larval worms live in the blood-vascular system, having gained this 

 location through the intestinal wall inmiediately after their ingestion. 

 It is at this stage that they produce the aneurysms as found in the vis- 

 ceral trunks of the posterior aorta. These aneurysms are usually some- 

 what elongate, with tunica media much thickened, and with fibrin 

 deposit upon the intima, on which a number of reddish tinted strongyls 

 are likely to be fixed. The aneurysm may, however, be entirely free 

 from worms, in which case they have probably passed with the blood- 

 current to the intestinal wall. 



Where death has occurred from thrombo-embolic coUc due to ver- 

 minous aneurysm, the most prominent alterations found are those which 

 have already been described in reference to this complication. The 

 intestines are usually much distended by gas, or, if rupture has occurred, 

 this, with more or less intestinal contents, will be in the abdominal 

 cavity. Extensive darkly discolored areas are usually observed in the 

 intestinal walls, and there are likely to be evidences of degeneration if 

 the course of the attack has been sufficiently prolonged. Owing to the 

 great engorgment of the mesenteric vessels, it is often difficult, without 

 the most searching examination, to discover the location of the embolus. 

 Rarely the immediate cause of death may be found to have been due to 

 rupture of the aneurysm and internal hemorrhage. 



Treatment. — For the strongyles in the intestine the same treatment 

 may be employed as has been recommended for the ascarids, though, 

 owing to the firm attachment of the former to the mucosa, their expul- 

 sion is difficult. Oil of turpentine has been recommended as particu- 

 larly valuable. It may be given in two to four ounce doses in oil. 



In prophylaxis clean water is a main factor. This should be filtered or 

 quite pure and free from drainage contamination. 



Sthongylosis of the Intestine of the Dog and Cat. 

 Ankylostomiasis 



1. Ankylostoma canina (Dochmius trigonocephalus ; Uncinaria tri- 

 gonocephala; U. canina). Fig. 156. Strongylinse (p. 280). — The body 

 is whitish in color and slender; sHghtly enlarged at the anterior extremity. 

 On the ventral surface of the buccal capsule are two chitinous plates, 

 each having three recurving teeth. The bursa of the male is three-lobed, 

 two large lateral and a small median. There are two long and slender 

 spicules. The vulva of the female is situated near the posterior third 

 of the body. 



The female is 10-20 mm. (3/8-3/4 of an inch) in length; male, 9-12 

 mm. (11/32-1/2 an inch). 



