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No. XVI. 



Memorandum concerning a new Vegetable Muscipula. By Dr. 

 Barton. 



Read February 18tli, 1S03. 



February, 16th, 1803. 



The existence of an irritable principle in vegetables waa 

 denied by Haller, by Gaubius, and by Wolf, but has been 

 completely demonstrated by the researches of many of the 

 botanists. This principle is now found to pervade almost every 

 part of the organized plant. It is particularly conspicuous in 

 the stamens and pistils, or male and female organs of genera- 

 tion, in vegetables. With respect to these organs, it would 

 indeed seem, that the irritability which they possess is almost 

 entirely subservient to the function of generation. 



In many vegetables, the irritable power is very remarkable, 

 and some tacts would lead us to believe, that it is accompa- 

 nied by the sense of perception. The wonderful faculty of 

 the Dionasa muscipula, one of the native plants of our coun- 

 try, is now pretty well known to every person who is studious 

 of the interesting subject of vegetable physiology. Each leaf 

 of the Dionaea is terminated by a glandular-like apparatus, 

 which immediately closes upon, and retains, the insect that 

 alights upon it. Something of the same kind has been dis- 

 covered in different species of Drosera, or Sundew. 



We are by no means acquainted with the extent of the 

 irritable principle in vegetables. It will, doubtless, be found 

 to pervade the vegetable structure much more generally than 

 is now supposed. In particular, we may expect to discover 

 instances of irritability in many vegetables, in which this attri- 

 bute has not, hitherto, been observed. In the summer of 

 1801, I discovered a vegetable muscipula in the vicinity of 

 Philadelphia. Having collected some branches, in flower, of 

 the Asclepias syriaca, or Syrian Swallow-wort, well known in 



