STRUCTURE.] 



ITS CHEMICAL COMPOSITION. 



351 



with that of certain Orchids. According to Fourcroy and 

 Vauquelin, the pollen of the Date tree consists of malic acid, 

 phosphate of magnesia and lime, and also of an insoluble 

 animal matter intermediate between gluten and albumen. 

 Macaire Prinsep has ascertained that the pollen of the Cedar 

 contains malate of potass, sulphate of potass, phosphate of 

 lime, silica, sugar, gum, yellow resin, and a substance which, 

 by its characters, approximated to starch. Being analysed 

 as a whole, it gave per cent., 40 carbon, 11- 7 hydrogen, and 

 48-3 oxygen, but no nitrogen. (Bibl. Univers. 1830, p. 45.) 



Pollen has been found to contain sugar, a yellow colouring 

 matter, gum, starch, a fixed oil, malic acid, phosphates, and 

 especially a peculiar, azotized, inflammable principle which is 

 insoluble in nearly every liquid and is called Pollenine. 

 (Girardin Lemons de Chimie Element air e, 3rd edn. p. 839.) 



Mr. Herapath gives the following as the results of his 

 examination of the pollen of the white and red lily, and of 

 Cereus speciosissimus : 



(Pharmaceutical Journal, 1848. February.) But we do not 

 see where the starch, which exists in all Pollen, appears. 

 Is it included in his Sugar, or Gum ? and what is this 

 Chemist's Extractive ? 



To this important part of the organisation of perfect plants, 

 attention has been directed with great care and skill by 

 numerous observers of the first class, among whom are 

 especially to be noticed R. Brown, Ad. Brongniart, Fritzsche, 

 Griffith, Mirbel, Mohl, and Schleiden. From their inquiries, 



