LIFE HISTORY OF ASCARIS LUMBRICOIDES. 33 



December 19, 1917 : Killed the last iiiuuse 296 days after I'eediu;^. A small, 

 encapsulated tumor, superficial, in liver near the margin contained degener- 

 ated lan'jB and a waxy or caseous substance. No definite calcific-ation. 



Experiment No. 5. 



June 23, 1917: Fed 12 wliite mice at 11 a. m. eggs of Ascaris suum on 

 bread, after starving 24 hour§. 



June 25, 1917 : Killed tlie first mouse 51 hours after feeding. In stomach 

 2 unhatched eggs ; in small intestine a few unhatched eggs. Lungs and spleen 

 negative. Liver heavily infested with larvae 0.28 to 0.33 mm. long. In large 

 intestine uniiatched eggs containing viable embryos. 



It is evident that within 51 hours large numbers of the larvge have lodged 

 in tlie liver, but apparently the lungs have not yet been invaded. It is in- 

 teresting to note that a number of eggs still remain in various parts of 

 the digestive tract and, apparently, are in the process of passing out, since 

 they are found fairly numerous in the large intestine. 



June 28, 1917 : Killed second mouse 5 days after feeding. Liver heavily 

 infested. Larvae from the liver were kept alive in salt solution for 24 hours, 

 but all died within 48 hours. Lungs, spleen, small and large intestines negative. 

 Larvae in liver measui'ed 0.28 to 0.34 mm. in length. 



June 29, 1917 : Third mouse died of pneumonia 6 days after feeding. In- 

 tense congestion and hemorrhage by diapedesis. No larvae in the liver, spleen, 

 or intestines, but very numerous in the lungs. Larvae in lungs measured 0.34 

 to 0.4 mm. in length. 



June 30, 1917 : Fourth and fifth mice died of pneumonia 7 days after 

 feeding. Lungs heavily loaded with larvae, 0.29 to 0.6 mm. in length. Other 

 organs not examined. 



July 2, 1917 : Sixth mouse died from pneumonia 9 days after feeding. Lungs 

 heavily infested with larvae, 0.56 to 0.86 mm. in length. Liver heavily in- 

 fested with larvae, 0.56 to 0.86 mm. in length. Small intestine, 3 larvae. Esoph- 

 agus, numerous larvae, 0.9 to 1.45 mm. in length. Spleen, 1 larva, 0.36 mm. long. 

 Cecum, 4 larvae, 0.38 to 0.46 mm. long. 



July 3, 1917 : Seventh mouse died 10 days after feeding. Lungs heavily in- 

 fested ; larvae 0.6 to 1.12 mm. in length. Small intestine, numerous larvae, 0.83 

 to 1 mm. in length. Large intestine, several larvae, 0.75 to 1.45 mm. in length. 

 Spleen negative. 



Most of the larvae remained actively motile in the tissues for 24 hours after 

 the animal died, but all larvae were apparently dead 48 hours after the death 

 of the host. 



July 5, 1917 : Killed eighth mouse 12 days after feeding. Lungs lieavily 

 infested. 



Of the 4 mice remaining 3 were lost track of and 1 was still alive June 5, 191S. 



Experiment No. 6. 



September 22, 1917 : Fed 6 white mice with eggs of Asca7'is suum on bread. 



September 24, 1917 : One mouse died 2 days after feeding. No larvae in 

 liver. 



September 29, 1917 : Second mouse died 7 days after feeding. Not examined. 



October 4, 1917 : Third mouse died from pneumonia 12 days after feeding. 

 Numerous larvae in lungs. Other organs not examined. Two mice born to one 

 of the mice ted September 22. 



