CELLS WITH SPECIFIC FUNCTIONS. 



87 



lining the vessel ; numerous dumb-bell shaped starch-grains are 

 also often present lying in the latex. 



Laticlferous cells are, strictly speaking, a form of idioblast. 

 They are large oval cells, the protoplasm of which manufactures 

 the milky secretion, the process being probably of the nature of 

 an oxidation or breaking-down of the cytoplasm. 



Fig. 71.— a, Spheroids of Inulin in a cell of Dahlia tuber, b, A 

 TANNIN-CELL lying amongst the cortical cells of Pinua stem, c, A 

 STELLATE IDIOBLAST formed at the junction of several strands of 

 "tubular" cells in the flower-stalk of Nymphcea. The nodules on 

 the wall are composed of oxalate of lime. 



