126 PREDACIOUS AND PARASITIC 



presents some points, which are capable of being ruptured by the 

 expanding fovilla, which, if it has the opportunity, penetrates, by 

 means of an extension, known as a ^'-pollen tube," the stigma of a 

 flower of its own kind, and effects the fertihsation of the ovules 

 contained in the ovary at the base of the style. 



From these circumstances we might expect that the semi-fluid 

 contents of the pollen grains would be of a highly nitrogenous 

 character, and would possibly contain also such elements as phos- 

 phorus and sulphur. 



The following analysis of " Pollen," by Schneider, given in the 

 Journal of the Chem. Soc, Vol. X., p. 175, shows that this expecta- 

 tion is well founded. 



Water 



Ash, chiefly Phosphates ... 



Albumin and Peptones ... 



Sugar 



Fats and Fatty Acids (colouring matter) 



Cell Membrane 



Pecten 



99-86 



Sachs states that fovilla consists of " coarse-grained protoplasm, 

 with grains of starch and drops of oil." Another authority states 

 that it consists of " starch granules, oil globules, and protein com- 

 pounds." From my own experience, I am inclined to think that 

 the sugar given in the above analysis should have been shown as 

 its equivalent of starch, from which it was probably formed in the 

 analytical process. The proteids are mainly, if not wholly, in the 

 form of albuminoids, and do not differ widely from the following 

 analyses of vegetable albuminoids, given by Lintner and Szilagyi 

 respectively : — 



Carbon .. 43-33 ... 44-50 



Hydrogen ... 6-98 ... 7-08 



Nitrogen 

 Sulphur 

 Oxygen 

 Ash 



9-92 ... 9-49 



1-07 ... I -08 



32-91 ... 32-95 



479 ••• 4"9 



