158 SAGACITY AND MORALITY OF PLANTS. 



tion of their moisture — a most important incident, 

 when we consider the long droughts occurring in 

 such countries. 



Even the milky juices exuded by the leaves of 

 the common Lettuce, Milk -thistle, etc., may be 

 frequently ranked among the defensive arrangements 

 of plants. Kerner narrates some experiments he 

 made which prove that ants, and other insects 

 crawling over such leaves, soon get glued down by 

 the milky exudations produced by the claws of their 

 tiny feet. His experiments were made with Lactuca 

 augustana and Lactuca sativa. He says : "No sooner 

 had the ants reached the uppermost leaves, or 

 the peduncles and the involucral bracts, than at 

 each moment the terminal hooks of their feet cut 

 through the epiderm, and from the little clefts thus 

 made milky juice immediately began to flow. Not 

 only the feet of the ants, but the hinder parts of 

 their bodies were soon bedrabbled with the white 

 fluid ; and if the ants, as was frequently the case, 

 bit into the tissue of the epiderm in self-defence, 

 their organs of mastication also at once became 

 coated over with the milky juice. By this the ants 

 were much impeded in their movements, and in 

 order to rid themselves of the annoyance to which 

 they were subjected, drew their feet through their 

 mouths, and tried also to clear the hinder part of 

 their body from the juice with which it was smeared. 

 The movements, however, which accompanied these 



