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LIFE HISTORY OF ASCARIS LUMBRICOIDES. ot 
Experiment No. 14. 
December 3, 1917: Fed three rabbits (with pipette) heavy doses of a 2 per 
eent formalin culture of Ascaris suum eggs. Culture started October 22. 
December 13, 1917: Ten days after feeding, one rabbit died. Lungs intensely 
hemorrhagie in the stage of red hepatization; extreme hemolysis. Blood thin 
and watery and would not coagulate after long standing. Thousands of larve 
throughout the lung tissue. Small pieces taken at random were always found 
swarming with worms. Laryze were also numerous in the trachea, esophagus, 
lungs, and stomach. The small intestine, liver, and spleen were negative. 
Measurements of larve in different organs as follows: Lungs, 0.9 to 1.8 mm.; 
stomach, 1.45 to 1.75 mm. 
February 27, 1918: Killed second rabbit 86 days after feeding. Two dead 
and encapsulated larvz seen in the lungs; none in the liver, spleen, trachea, 
esophagus, or small intestine. Lungs showed a few petechize but otherwise were 
normal in appearance. 
March 12, 1918: Third rabbit died from pneumonia (not verminous) 99 days 
after feeding. No larve seen in liver, lungs, trachea, esophagus, or spleen. 
Other organs not examined. 
Experiment No. 15. 
July 8, 1918: Fed 3 rabbits with eggs of Ascaris suum incubated since April 
4, 1918. 
July 6, 1918: Killed first rabbit 3 days after feeding. Numerous larve in 
liver, 1 in lungs, 1 in trachea. Spleen negative; other organs not examined. 
Parasites in liver, 0.2 to 0.25 mm. One in trachea measured 0.23 mm. 
July 8, 1918: Killed second rabbit 5 days after feeding. Larvze in liver and 
lungs. Spleen, trachea, and esophagus negative. Other organs not examined. 
Larve in liver (4 specimens), 0.23 to 0.45 mm. Larvee in lung (9 specimens), 
0.23 to 0.48 mm. 
July 11, 1918: Third rabbit died 8 days after feeding. Liver negative, lungs 
heavily infested with larve, 1 in trachea, 3 in esophagus, 1 in small intestine, 1 
in stomach, Larve in lungs (13 specimens), 0.33 to 0.73 mm.; trachea, 0.75 
mm.; stomach, 0.6 mm.; esophagus (3 specimens), 0.99 to 1.38 mm. 
Experiment No. 16. 
December 3, 1917: Rabbit fed eggs of Ascaris suum. 
December 13, 1917: Rabbit died; lungs heavily infested. The lungs were 
eut into small pieces, placed in artificial gastric juice in the incubator and the 
larve digested out of the tissues. . 
December 14, 1917: Larve removed from the digestive fluid and placed in 
normal salt solution at room temperature, 
December 17, 1917: Some larve still alive. 
December 26, 1917: Some larve still alive. 
January 4, 1918: Next examination, all dead. 
Experiment No. 17. 
Several years before the present series of experiments, the junior writer 
attempted to infest hogs by feeding one lot with the eggs of Ascaris suum, a 
second lot with eggs of Ascaris lumbricoides, and reserving a third lot as check 
animals. The different lots were kept in separate pens on ground where no 
pigs had ever been before. The feces of all the pigs were previously examined 
for Ascaris eggs and found free. At the end of about three months the pigs 
which had been given eggs of Ascaris lumbricoides were found positive, those 
