424 



POPULAR SCIENCE MONTHLY. 



with it here, as in the stomachs of animals, a coagulating principle, a 

 rennet. In some manner difficult to guess the shepherds of the Alps 

 learned years ago that the leaf of the butterwort placed in fresh milk 

 would cause it to thicken rapidly, and to this day they use these leaves 

 rather than the animal extract in the making of curd for cheese. 



Fig. 7. The California^ Pitcher plant. The white spots are the fal«e windows, and in 

 the head to the left, which has been torn open, may be seen the mouth, situated just behind the 

 hanging appendage. 



The stui-dew (Drosera) is one of the best known of the insectivo- 

 rous plants of this class, both because of the wide distribution of the 

 ninety species over the world and on account of the detailed and 



patient study of it which was made by Darwin, whose 



IOO| 



Insectiv- 



orous Plants' is a rich mine of information for any one interested in 



