300 THROUGH THE FIELDS WITH LINNAEUS 



lantern ; or rather he re-awakene J them, for the simili- 

 tude which plants bear to animals was partially the basis 

 of his system. Linnaeus was the father of compara- 

 tive physiology. This discovery awakened a new ^ain 

 of ideas, a glimpse into Nature's most secret operations. 

 The sleep of plants is regular like that of animals. 

 ' Though,' as Balfour says, ' what has been called by 

 Linnaeus ike sleep of plants is the change produced on 

 leaves by the absence of light, it is by no means analo- 

 gous to the sleep of animals. During darkness some are 

 slightly twisted, and hang down ; others, such as pinnate 

 and ternate leaves, have the leaflets folded together, and 

 frequently the common petiole depressed. The youngest 

 leaflets first exhibit these changes, and when the plants 

 become old, and their tissues hardened, their irritability 

 is often much diminished, as in the oxalis.' The leaves 

 of many plants follow the sun in his daily course clover, 

 for instance. How Linnaeus must have enjoyed the de- 

 scription of the slender iris, abundant on the Morocco 

 coast (J. Sisyrhynchium of Linnaeus), whose delicate 

 flowers last only a few hours, opening one at a time on 

 successive days, appearing about midday, and withering 

 in the afternoon. 1 



In his ' Pan and Pandora,' dated about this time, 

 Linnaeus set forth what vegetable every animal and 

 insect eats. Few persons besides Ray, he says, have 

 considered plants in their rural oeconomy. 



The King of Sweden commenced in 1751 a natural* 

 1 Sir J. Hooker. 



