14'4 SENSIBLE PERSPIRATION. 



water trickle from their leaves like a slight shower of 

 rain. Sometimes it is of a saccharine nature, as De la 

 Hire observed in Orange trees ; Du Hamcl Arb. v. 1. 

 1,50. It is more glutinous in the Tilia or Lime-tree, 

 more resinous in Poplars, as well as in Cist us creticus, 

 from which last the resin called Labdanumis collected, 

 by beating the shrub with leather thongs. See Tour- 

 nefort's Voyage, 29- In the Fraxinella, Dictammts 

 idbuSy it is a highly inflammable vapour. Ovid has 

 made an elegant use of the resinous exudation of 

 Lombardy Poplars, Populus dilatata, Alt. Hort. Kew. 

 v. 3. 406, which he supposes to be the tears of 

 Phaeton's sisters, w r ho were transformed into those 

 trees. Such exudations must be considered as effu- 

 sions of the peculiar secretions ; for it has been ob- 

 served that Manna may be scraped from the leaves of 

 Fravinus Ornus, FL Grcec. t. 4, as well as procured 

 by incision from its stem. They are often perhaps a 

 sign of unhealthiness in the plant ; at least such ap- 

 pears to be the nature of one kind of honey-dew, to 

 which the Beech in particular is subject, and which, in 

 consequence of an unfavourable wind, covers its leaves 

 in the form of a sweet exudation, similar in flavour to 

 the liquor obtained from its trunk. So likewise the 

 Hop, according to Linnaeus, Faun. Suec. 305, is af- 

 fected with the honey-dew, and its flowers rendered 

 abortive, in consequence of the attacks of the cater- 

 pillar of the Ghost Moth, Phalana Humuli, upon its 

 roots. In such case the saccharine exudation must 



