116 THE FLEA 



The animal can then be killed by tapping its head or 

 breaking its neck from the outside of the bag. After 

 this has been done, fleas may be searched for in the 

 fashion described above. 



Most of the small mammals which act as hosts for 

 fleas are nocturnal. The localities where they may 

 be trapped are numberless, but only a small propor- 

 tion of the captures may yield anything for the 

 flea-collector. I have heard of a collector of small 

 mammals who travelled through remote parts of Spain 

 and never lost an occasion for putting down his traps 

 when he had to change trains at a country railway 

 junction. In England it would, however, seldom be 

 worth doing this, as, on many lines, there is an attempt 

 to make the arrival of one train and the departure 

 of another correspond. 



The following plan for securing bird-fleas will be 

 found successful. The nests of birds should be taken 

 as soon as the young are fledged and flown. If the 

 nest is small it can be put into a glass-topped box 

 lined with white paper. If too large, the whole nest, 

 or the most firmly matted and dirty part, may be put 

 into a glass globe (such as gold-fish are kept in) and 

 a piece of paper tied over the mouth. From time to 

 time the nest should be slightly damped with water. 

 In every case a label should be put into the receptacle 

 to preserve the name of the bird which built the nest. 

 The bottom of the nest may sometimes be seen to be 



