PERSPIRATION OF PLANTS. 3 



male parts of fructification of the common polypody, 

 and soon after of the wall-rue, discovered under the 

 cuticle of their leaves, (whether fruit-bearing or 

 not) oval bodies, containing a sort of granulated 

 matter, and each having an aperture, with which 

 vessels communicated. These bodies, however, he 

 mistook for the male organs of ferns, and after- 

 wards gave a long description of them, and of 

 their method of impregnating the females, to- 

 gether with a good figure, in his New botanical 

 Discoveries.* 



Geneve 1762. 1a :" which, being very scarce, and containing much 

 observation unconnected with theory, deserves the more to be reprinted- 

 It was not Von Gi. EicHEN,but this ingenuous philosopher of Geneva, 

 who first pointed out the remarkable structure of the membranes that 

 cover the leaves and petals of plants. What he calls ecorce he found to 

 consist of two distinct membranes, the undermost of which was stiled by 

 hint Reseau cortical or l'ccorce proprenient dite, to distinguish it from 

 the upper cuticle, adhering so closely to it, that a separation can seldom 

 be effected either by boiling or maceration. The latter, which he calls 

 epidermis in the strict sense, and to which also Hedwio alludes, is, 

 according to his observations, unorginized, perfectly transparent, and 

 analogous to the epidermis or scarf skin of the human body; while the 

 subjacent membrane, which perhaps may be compared to the organized 

 cutis in man, he found provided with those ducts and oblong bodies 

 (his glandes corticales) which Gleichen and Hedwig discovered after him, 

 and which constitute the subject of the above dissertation. T. 



* Das ncueste aus dem Rciche dcr Pflanzen, &c. i. e. New discoveries 

 in the vegetable kingdom, by W. Fr.Von Gleichen, 1764.fol.p- 34 — 30 T. 



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