98 PARASITOLOGY. 
animals, principally the young. 
Under the family Ascaridae is placed the genus 
Ascaris. They are not blood suckers. 
ASCARIS MEGALOCEPHALA (Megalo—large ; Cephale—head). 
Synonym.—Ascaris Equorum. 
Distribution.—Widely distributed; common in the 
United States. 
Description.—This is the largest species of the 
.family Ascaridae. The body is as large in calibre as 
a lead pencil; its color is a yellowish white and itis 
marked with transverse ridges; the head is distinct 
and is provided with three lips; the tail of the male 
is straight and it is provided with small lateral mem- 
branous wings and 80 to 100 papillae. In the female 
the vulva is located in the anterior one-fourth of the 
body. The male measures eight to ten inches; the 
female ten to twelve inches; the female is ovipa- 
rous Animals Intested.— 
The horse, the ass and 
the mule. 
Parts Infested. — The 
small intestines. 
Symptoms.—They are 
found free in the small 
intestines and consume 
food taken in by the 
host and digested ; thus 
they rob the host of its 
nutrients. By their 
“@ presence they may cause 
various troubles of di- 
Fig. 34.—ASCARIS MEGALOCEPHALA (a gestion : they may cause 
yamngiane a catarrhal condition of 
: a a Lips. the small intestines, and 
the irritation may be 
