LIFE HISTORY OF ASCARIS LUMBRICOIDES. 37 



Experiment No. 14. 



December 3, 1917: Fed three rabbits (with pipette) heavy closes of a 2 per 

 cent formalin culture of Ascuri.s fniutn eggs. Culture started October 22. 



December 13, 1917: Ten days after feeding, one rabbit died. Lungs intensely 

 hemorrhagic in the stage of red liepatization ; extreme hemolysis. Blood thin 

 and watery and would not coagulate after long standing. Thousands of larvae 

 throughout the lung tissue. Small pieces taken at random were always found 

 swarming with worms. Larvae were also numerous in the trachea, esophagus, 

 lungs, and stomach. The small intestine, liver, and spleen were negative. 

 Measurements of larvne in different organs as follows: Lungs, 0.9 1o 1.8 mm.; 

 stomach, 1.45 to 1.75 mm. 



February 27, 1918 : Killed second rabbit 86 days after feeding. Two dead 

 and encapsulated larvae seen in the lungs ; none in the liver, spleen, trachea. 

 esophagus, or small intestine. Lungs showed a few petechiae l)nt otherwise were 

 normal in appearance. 



March 12, 1918 : Third rabbit died from pneumonia ( not verminous ) 99 days 

 after feeding. No larvae seen in liver, lungs, trachea, esophagus, or spleen. 

 Other organs not examined. 



Experiment No. 15. 



July 3, 1918 : Fed 3 rabbits with eggs of Ascans suuin incubated since April 

 4, 1918, 



July 6, 1918: Killed first rabbit 3 days after feeding. Numerous larvte 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. Larvae in liver and 

 lungs. Spleen, trachea, and esophagus negative. Other organs not examined. 

 Larvae in liver (4 specimens), 0.23 to 0.45 mm. Larvae 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 larvje, 1 In trachea, 3 in esophagus, 1 in small intestine, 1 

 in stomach. Larvae in lungs (13 specimens), 0.33 to 0.73 mm.; trachea, 0.75 

 mm.; stomach, 0.6 mm.; esophagus (3 specimens), 0.99 to 1.33 mm. 



Experiment No. 16. 



December 3, 1917 : Rabbit fed eggs of Ascans suum. 



December 13, 1917 : Rabbit died ; lungs heavily infested. The lungs were 

 cut into small pieces, placed in artificial gastric juice in the incubator and the 

 larvae digested out of the tissues. 



December 14, 1917 : Larvae removed from the digestive fluid and placed in 

 normal salt solution at room temperature. 



December 17, 1917 : Some larvae still alive. 



December 26, 1917 : Some larvae 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 Asearis suum. a 

 second lot with eggs of Asearis Imnhricoides, 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 Asearis eggs and found free. At the end of about three months the pigs 

 which had been given eggs of Asearis lumhricoides were found positive, those 



