20 NATURAL HISTORY ESSAYS 



shed blood. Peptone also (or the albumoses adhering 

 to it) injected into the blood-stream (•5 gram per kilo 

 according to Schmidt Miilheim) will prevent clotting 

 in dogs, but not in rabbits, a substance being formed 

 in the plasma, and many of the white blood corpuscles 

 beinof dissolved. Now when one recollects that 

 histologically the pancreas is but an immense salivary 

 gland, the probability of the vampire saliva containing 

 a hsemolytic agent is distinctly increased; for it 

 may contain a body analagous to the tryptic ferment 

 of the pancreas already mentioned. This research is 

 of considerable academic interest, and perhaps also of 

 practical value, since it may be possible to discover 

 some improved method of dealing with the bites ot 

 vampires. In this connection it is well to remember 

 how Science by attacking the apparently insignificant 

 mosquito has lessened the ravages of malaria, and 

 how the recent study of the tse tse fly (itself a bane 

 to cattle) has been the key to the study of the 

 sleeping sickness of Uganda. The lower animals 

 deserve serious attention, from the indirect influence 

 they may exercise upon man. The plague-stricken 

 rat, the oyster which spreads typhoid, and the 

 blowfly that transmits blood-poisoning cannot with 

 impunity be left out of account; hence it may be far 

 from unprofitable for some experienced naturalist to 

 prosecute with skilled enthusiasm the study of the 

 brown harpy of the Amazon forests — the vampire 

 bat. 



