LECT. VIII. OF PLANTS. 175 



is very desirable that the observations of Quatrefage should 

 be confirmed and varied. 



Phosphorescence of Plants. Botanists assert, that in many 

 plants inflorescence is accompanied by phosphorescence. 

 But this phenomenon is, also, too rare to be capable of be- 

 ing properly studied. During the period of inflorescence, 

 oxygen is absorbed and carbonic acid disengaged ; in a 

 word, there is combustion, and this is the reason why in 

 certain cases of inflorescence considerable heat is developed. 

 Perhaps, also, some volatile oil, separated from the flower 

 at the ordinary temperature, may be the cause of this light. 



