1 14 Ohservallons concerning 



I feel nuicli obligtd to Dr. Smith for leading me, by the 

 preceding observations, to pay a more critical attention than 

 I might otherwise have done to the oeconomy of the Sar^ 

 racenice and other ascidial plants. Hitherto, hou'ever, 1 

 have not observed any spe ies of Spht:x, or of Jchnewnoiif 

 entraffed in the singular business which he has mentioned. 

 And although I do not doubt tb.af the gardener's statement 

 is in the main correct, yet I incline to thmk that the sup- 

 posed Sp/iex, or Ichneumon, was an insect of some other ta- 

 mily. Future observations will, I hope, enable me to de- 

 termine this point entirely to my suisfaction. 



Alihough [ liave no doubt thai , 'anls mav derive much 

 of their nutriment and strength i i iheehments of de- 

 composed animal bodies, just as i. ^uppoie that innume- 

 rable species of animals are nourished by inorjranic matter; 

 and although it is possible that the air evolved by the dead 

 insects in the ascldia of the Sanaceuice and other similar 

 plants may contribute somewhat to the vegetation of these 

 plants, yet 1 cannot suppose that the final intention of 

 Nature in furnishing plants with ascidial leaves Is to lay up 

 a store of nutritious aliment for the plant. 



So far as the species of Snrractnia are concerned in this 

 view of the subject, I hardly know any plants to which 

 such storehouses as we are speaking of would be less ne- 

 cessary. For they live in the midst or upon the margin of 

 marshes, where animal matters of various kinds are con- 

 tinually putrcfvine, and v^here of course the plants are al- 

 most conslanlly surrounded by an atmosphere of azotic and 

 hydrogen gases. 



Again, the wonderful £)w??<2'« Mnscipi/la, the extremities 

 of whose leaves entrap, and frequently retain for a consi- 

 derable time, various small species of insects, resides only in 

 marshy eroumls, not much unlike those just mentioned. 

 In this plant, it appears to me to be still more difficult to 

 o-ive a plausible guess abont the intention of Nature in 

 constructing these vegetable Muscicapce, than in regard to 

 the Sarracenice. 



If, however, we were acquainted wiih only the last-men- 

 tioned veoetabies, with Neptntkcs and with Dioiiceu, as the 

 only plants, I say, endued with the power, however difterent 

 the means, of catching or entrapping insects, we nnght, 

 perhaps, with some decree of reason miagine that this fa- 

 culty is, somehow or other, subservient to the business of 

 vco-etable n'ltritlon. But never can this Idea be extended, 

 with even the iaintest shado - of a good theory, to those 

 truly Irritable Aluscicapce, ylpocynum androsannifuUam, 



uiiclepiaa 



