510 MEDICAL ENTOMOLOGY 



the tube ; the bugs, never more than fifteen or twenty in number, are 

 then dropped on to the paper and the tubes are placed upright in a 

 small jar, which is kept in a tray of water. It is generally believed 

 that the bed bug is unable to crawl up a smooth surface such as the 

 side of a glass ; this, however, is not true, and if the tubes are not 

 plugged with cotton wool some of the bugs will be found at the 

 bottom of the jar, having crawled out of the tube ; dead ones may 

 even be found in the water. If regularly fed they do not often 

 attempt to leave the tubes. 



The filter paper should be regularly changed, as it soon becomes 

 saturated with the fluid excreta and then develops moulds, and if 

 this is allowed to happen the bugs will become infected. To accomplish 

 this the paper with the bugs on it is drawn out of the tube with a 

 pair of forceps, care being taken not to crush any eggs which may have 

 been laid on it ; the paper is placed in the centre of a large white enamel 

 tray ; if not disturbed the bugs do not make any attempt to leave the 

 paper. The tube is now carefully cleaned, first washing it out with water 

 and then wiping it with some 1 in 20 carbolic acid ; it should be thorough- 

 ly dried until there is no smell of the carbolic left. To replace them 

 each bug is grasped with a fine pair of forceps lightly across its 

 abdomen, and dropped on to the fresh paper at the bottom of the tube 

 by tapping the forceps against the edge of the glass. In this way 

 all the bugs can be changed in a very short time, and there is little or no 

 danger of any of them escaping. If there are any eggs on the old piece 

 of paper it should be placed at the bottom of a glass jar which is 

 standing in water. As soon as the larvae hatch out they are transferred 

 to another tube containing some fresh filter paper. This is accomplished 

 with the aid of a fine brush, never with forceps; the larvae are easily 

 brushed up and then placed on the paper in the tube. After many years 

 of experience this has been found to be the most satisfactory way of 

 breeding and keeping bugs, and if the paper is regularly changed and 

 all dead bugs removed, the majority will live for long periods. 



Both the adults and immature stages can be readily fed if kept in 

 the above way. It is only necessary to draw the filter paper on which 



they are resting to the mouth of the tube, and then 

 Method of feeding , ., , . , . , . . 



bugs invert it over any part of the skin of the select- 



ed host. In a very short time they will crawl down 

 to the skin and begin to suck blood. The adults and nymphs never 

 leave the paper, but remain resting on the edge while they feed; the 

 larvae, on the other hand, very frequently leave the paper and crawl 



