LIFE HISTORY OF ASCARIS LUMBRICOIDES. 4] 
in regard to the first pig which died of verminous pneumonia. The heavy 
infestation in this case could not conceivably have resulted in any other way 
than from the massive dose of eggs given 7 days before. In regard to the 
second pig which was found infested with intestinal ascarids 44 days after 
the initial feeding of eggs, it is less certain that the worms came from the eggs 
that were fed. Yet the fact that all the worms found were of nearly the same 
size and, assuming that it takes about 24 months for adults to develop in the pig, 
as it has been shown is necessary in the case of the human Ascaris, the facts that 
the worms were immature and of a size that might reasonably be expected after 
44 days of growth, are not inconsistent with the presumption that the worms 
found came from the eggs that were fed to the animal. 
Experiment No. 20. 
Two young suckling pigs were used, one fed with eggs of Ascaris lumbri- 
coides containing vermiform embryos, the other reserved as a check animal. 
Both pigs and the sow were transferred to a clean board pen soon after the 
pigs were born and the feces of the sow were frequently examined for evidences 
of Ascaris infestation. Throughout the experiment the feces were negative. 
Highty-one days after the feeding with Ascaris eggs the pig was slaughtered but 
no Ascaris was found in the small intestine nor in any of the organs usually 
invaded by the larve. Seventeen days later the check animal was slaughtered 
and was also found free from Ascaris infestation. Some of the same culture of 
eggs used in this experiment was fed to guinea pigs, whose lungs became 
heavily infested with larvee, so there is no question as to the viability of the 
eggs. 
Experiment No. 21. 
In this experiment 5 newborn pigs were used, date of birth, March 22, 1917. 
Three pigs were fed with the same culture of eggs used in Experiment No. 20, 
and 2 pigs were kept as checks. All 5 were kept with the sow in a recently 
built clean pen. 
March 30, 1917: First pig received about 5 c. c. of a culture of eggs of Ascaris 
lumbricoides. Second pig received about 6 c. c. Third pig received about 4 ec. e. 
April 8, 1917: Pig No. 2 died 9 days after feeding. The lungs were spotted. 
with numerous ecchymoses but not intensely hemorrhagic as in laboratory ani- 
mals dying of verminous pneumonia. The spleen and thyroid were negative. 
One larva was found in the liver, the lungs were heavily infested, larvz were 
numerous in the trachea, while one larva was found in the pharynx and one 
in the esophagus. Larve in the trachea varied from 0.85 to 1.04 mm. in length, 
with esophagus from 0.09 to 0.13 mm. long. 
May 6, 1917: Sow removed from the pen. While with the pigs four fecal 
examinations were made at intervak, all of which proved negative. 
June 8, 1917: First pig slaughtered and examined 65 days after feeding. 
Lungs showed lesions of broncho-pneumonia. There were 2 large hemorrhagic 
areas in which 2 degenerated Ascaris Jarvzee were seen. Trachea, esophagus, 
stomach, intestines, spleen, and liver were negative for Ascaris. 
July 5, 1917: The third pig was slaughtered 97 days after feeding. Lungs, 
bronchi, trachea, esophagus, small and large intestines were all examined, but 
no Ascaris found. 
July 17, 1917: Fourth pig (check animal) slaughtered and examined 109 days 
after feeding pigs 1, 2, and 3. Negative for Ascaris. 
July 26, 1917: Fifth pig (second check animal) slaughtered and examined 118 
days after feeding pigs 1, 2, and 3. Negative for Ascaris. 
