638 MEDICAL ENTOMOLOGY 



shown in the photograph) rests on a ledge on the inside, and serves 

 as a foot rest when one is required ; underneath this there is a tray or 

 underpan made of galvanized iron, to catch the urine or faeces when 

 the cage is used for a small animal. Such cages are inexpensive, and 

 have the great advantage that they can be sterilized by immersing them 

 in boiling water, to kill off eggs, larvae, etc., which may be in the crevices 

 and would interfere with experiments. They can be painted to prevent 

 the metal rusting. These cages, with larger ones of the same pattern, 

 were devised by Major Christophers for dogs used in experiments with 

 ticks and Piroplasma cams. 



For experiments with Argas persicus, the wire foot rest and underpan 

 are removed, and the cage is placed in a strong white cloth bag, made to 

 fit it and fastened at the top with a running tape. The head of the fowl 

 is enclosed in a muslin bag secured with a purse string, the tapes being 

 crossed and tied under the wings, to prevent it from eating the ticks, of 

 which most fowls are very fond. The larvae are dropped either on some 

 clean straw placed in a corner of the cage, or placed under the wing 

 of the fowl. The bird is then placed inside the cage, which should be 

 protected from ants by placing it on a table the legs of which are 

 standing in antiformicas. Only a moderate number of ticks should be 

 placed in each cage, or they will kill the host from loss of blood. If the 

 experiment is allowed to go on indefinitely through several generations of 

 ticks the cage will literally swarm with them. 



At least once a day the host is removed from the cage and given 

 food and water, care being taken that it does not rid itself of its 

 parasites while it is at liberty, which it will certainly attempt to do if 

 it is not watched. The larvae drop off when full-fed, and collect in the 

 crevices of the framework of the cage. When all the larvae have left the 

 host the latter should be removed, and the bag changed. As soon as the 

 first nymphs appear, as will be readily seen by examining the cage, the 

 fowl is replaced for two successive nights and after this at intervals of 

 a week or ten days. 



In order to experiment with Argus vespertilionis it is necessary to 



obtain one of the several species of bat on which it feeds, and to devise 



some method of keeping it in captivity for a consid- 



Argas vesperti- erable time. The roosting places of Scotobhilus ktthli 

 lionis : Breeding , , , , ,. . . . ... , , 



technique one hosts of this tick in Madras are holes in 



banyan trees ; on locating one, a large butterfly net is 

 held over the outlet about the time the bats are accustomed to come 

 out in the evening ; the bats fall into it as they fly out. They should be 



