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contracted to restrain evaporation. Linnaeus conceived this plant to 

 be allied in constitution to Nymphsea, and consequently to require a 

 more than ordinary supply of water, which its leaves were calculated 

 to catch and to retain, so as to enable it to live without beinsr 

 immersed in a river or pond. But the consideration of some other 

 species renders this hypothesis very doubtful. S. flava, t. 780, and 

 more especially S. adunca, Exot. Bot. t. 53, are so constructed that 

 rain is nearly excluded from the hollow of their leaves, and yet that 

 part contains water, which seems to be secreted by the base of each 

 leaf What then is the purpose of this unusual contrivance } An 

 observation communicated to me in 1805, in the botanic garden at 

 Liverpool, seems to unravel the mystery. An insect of the Sphex or 

 Ichneumon kind, as far as I could learn from description, was seen 

 by one of the gardeners to drag several large flies to the Sarracenia 

 adunca, and, with some difliculty forcing them under the lid or cover 

 of its leaf, to deposit them in the tubular part, which was half filled 

 with water. All the leaves, on being examined, were found crammed 

 with dead or drowning flies. The S. purpurea is usually observed to 

 be stored with putrefying insects, whose scent is perceptible as we 

 pass the plant in a garden ; for the margin of its leaves is beset with 

 inverted hairs, which, like the wires of a mouse-trap, render it very 

 diflicult for any unfortunate fly, that has fallen into the watery tube, 

 to crawl out again. Probably the air evolved by these dead flies may 

 be beneficial to vegetation, and, as far as the plant is concerned, its 

 curious construction may be designed to entrap them, while the water 

 is provided to tempt as well as to retain them. The Sphex or Ich- 

 neumon, an insect of prey, stores them up unquestionably for the food 

 of itself or its progeny, probably depositing its eggs in their carcases, 

 as others of the same tribe lay their eggs in various caterpillars, which 

 they sometimes bury afterwards in the ground. Thus a double pur- 

 pose is answered ; nor is it the least curious circumstance of the 

 whole, that an Europaean insect should find out an American plant in 

 a hot-house, in order to fulfil that purpose." — Ed. 6 (1827), p. 156. 



As to the Nepenthes, no very positive statement can be given : but 

 it is certain, that of the fluid which is contained in the pitchers, a 

 portion at least is secreted by the plant itself, since the pitchers have 

 been found to contain fluid while yet in a very immature state, and 

 before the first opening of the lid. The interior is clothed with 

 downy hairs ; and it is probable that these perform the same functions 

 as in other cases, namely, those of attracting or secreting moisture by 

 the numerous points. The lid of the pitcher is closed in dry weather, 



