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VIII. On the Power of Sarracenia adunca to entrap Insects. In a 

 Letter to Sir James E. S?nith, Pres. Lmn.Soc, from James Mac- 

 bride, M.D. of South Carolina. 



Read December 19; 1815. 

 Sib, 



Your remarks on the oeconomy of the Sarracenia in your Intro- 

 duction to Botany, led me to think of making this communication ; 

 and I was emboldened to undertake it from having observed in 

 your prefatory remarks on the study of this science, a spirit of pe- 

 culiar liberality and disinterestedness. My object is to lay before 

 you the result of my observations on the insect-desti'oying-process 

 carried on by the tubular leaves of these plants. 



It will hardly be necessary to inform you that the Sarracenia 

 ftava and S. adunca (S. minor of Walter, and S. variolaris of Mi- 

 chaux,) grow in the flat countr}' of this state in great abundance. 

 With the latter my experiments have been chiefly conducted. If, 

 in the months of May, June, or July, Avhen the leaves of these 

 plants perform their extraordinary functions in the greatest per- 

 fection, some of them be removed to a house and fixed in an erect 

 position, it will soon be perceived that flies are attracted by them. 

 These insects immediately approach the fauces of the leaves, and 

 leaning over their edges appear to sip with eagerness something 

 from their internal surfaces. In this position they linger; hut at 

 length, allured as it would seem by the pleasure of taste, they 

 enter the tubes. The fly which has thus changed its situation, 

 will be seen to stand unsteadily, it totters for a few seconds, slips, 



and 



