NOTES ON PEDICULUS VESTIMENTI. 273 



quent efforts to escape under the edge of the glass ring in which 

 they were confined. (Normally they feed quietly and make no 

 effort to escape.) After the first moult they fed much more 

 normally. 2 died before the first moult. I died before the sec- 

 ond moult. 3 died just after the second moult. 



The remaining four had the third moult between March 1-4 



(3?, i c?). 

 Eggs Deposited: 



March 4th i 



March sth 3 



March 6th 6 



10 (Illness of the host closed the experiment.) 



Hatched: 3. 



Results: Although the lice do not bite normally and do not re- 

 produce normally the toxic effect of the quinine is not suffi- 

 ciently injurious to eliminate them. 



The most promising result is the very evident effort of the 

 young nymphs to escape and in view of the well-known perf- 

 sistent assertion that lice avoid some healthy people and leave 

 hosts who have contracted certain diseases, it is possible that this 

 effort to escape may indicate a distaste of the blood which may 

 cause lice to leave a host who is taking quinine. 



The Reaction of Lice to the Blood of the Host wJw is Taking 1 



Potassium lodid. 



Host: Helen P., age 25 years. 



Potassium lodid: Saturated solution in water. Five drops 

 three times daily. Prescription by Col. R. P. Strong. 



No. of Lice: Four males and four females. Collected from 

 healthy woman at St. Louis Hospital, April 2, 1919. The lice 

 were fed one hour daily. Their behavior during the feeding 

 hour was not normal. After feeding 10 or 15 minutes they 

 fought at intervals during the entire hour, though they never ap- 

 parently injured each other. The combatants were either two 

 males, two females, or a male and a female. They seize each 

 other by the head and thorax and it is frequently very difficult 

 to separate them. After seven days feeding on the presumably 

 medicated blood, the eggs were collected daily until 104 were de- 



