322 KENNEL DISEASES. 
large intestine, —where the excreta accumulates before being expelled, and 
from which waste matter they derive their nourishment. 
The ova or eggs from which they are hatched are produced in immense 
numbers. These may be taken into the stomach with the food and drinking- 
water, while the coat is being licked and itching parts bitten, and likely in 
various other ways. The gastric juice dissolves the envelope or shell covering. 
Thus set free, the young quickly pass downward into the intestine, where they 
develop so rapidly that they are quite mature before they have reached their 
abiding-place, also endowed with a vitality that is remarkable. 
Itching is the symptom excited by these worms that is likely to first attract 
attention. It is not, however, equally severe at all times. If a dog is often 
1. A Female Oxyuris Vermicularis, displaying the normal position of the digestive and reproduc- 
tive organs, and the points at which their several outlets terminate. Magnified about 12 diam. 2. Oral 
extremity of the same, showing the partly protruded lips, the lateral ale, pharyngeal muscles. Mag- 
nified about 300 diam. 3. Section from the lower part of the body, exhibiting the mode of termina- 
tion of the intestinal canal, and numerous ova lodged within, in the folded extremity of one of the 
uterine horns. Magnified about 150 diam. 4. Four ova: a, showing the commencement of the embry- 
onic formation, and 4, c, d, the completed tadpole-shaped embryo in their interior. Magnified about 
300 diam. (Cobbold.) 
seen dragging his hindquarters over the floor or ground, and biting the parts. 
adjacent to the outlet of the bowel, there is reason for suspecting thread-worms ; 
and if the subject be infested by them, they can be found in the intestinal dis- 
charges, often in great numbers, and sometimes agglutinated with mucus into. 
feculent balls. 
They are generally well down in the large intestine, in the lowest part of 
it —the rectum, —and only a short distance from the anus. From this they 
sometimes crawl out; and may cause bitches special annoyance by entering: 
