106 PARASITOLOGY. 
group of worms whose heads are provided with three 
small lips. The body is rather heavy and in the 
female the tail is long and attenuated. The males 
are provided with spiculae and two pre-anal papillae, 
and a rudimentary caudal pouch. 
The Oxyuridae are not blood suckers. 
Under the family Oxyuridae is placed the genus 
Oxyuris. Fav, 
Oxyuris CuRVULA (Oxys—pointed; oura tail). 
Synonym.—Pin worm; maw 
worm; curved Oxyuris. 
Distribution.— Very common in 
the United States. 
Description.—The body is whit- 
ish in color and rather thick; the 
head is blunt and is provided with 
three lips; the tail of the female 
aoe is long and attenuated ; the vulva 
vuta (Female). 18 located in the anterior third of 
a, Cephalic extremity. the body. The male is provided 
b, Caudal extremity. P ‘i 
with a rudimentary caudal pouch 
and one spicula; the posterior extremity is blunt. 
The male is from one-half to three-fourths inch in 
length; the female is from one to one and one-half 
inches in length; the female is oviparous. 
Animals Intested.—'The horse, the ass and the mule. 
Parts Intested.—Throughout the length of the large 
intestine and the rectum. 
Condition Produced.—Their presence in large num- 
bers -auses considerable irritation, which results in 
- catarrhal state. After evacuation of the bowels 
there is noted a small quantity of thick, whitish fluid 
around the anus (the product of catarrh) which dries 
