VIII.] . THE BEAN-PLANT. 83 



a. It contains four chambers, two on each side of 

 the continuation of the filament, and in each 

 chamber lie numerous pollen-grains. 



5. The pistil 



a. It is found by tearing open the stamen-tube: it 

 is a long green tapering body, somewhat flattened 

 laterally and ending in a point (the style) 

 which bears a tuft of strong hairs. 



k Slit it open carefully: in it lies a central cavity, 

 containing a number of small oval bodies, the 

 ovules, attached along its ventral side by short 

 pedicles. 



c. It is difficult to get a section of a bean-ovule, but 

 its essential structure may be readily made out 

 by making thin transverse sections of the ovary 

 of a large lily (where the ovules are closely im- 

 bedded in a large quantity of parenchyma) and 

 examining with 1 inch obj. 



a. The central cellular portion of the ovule 

 (nucleus) made up of a large number of cells. 



/& Its two coats, an inner (primine) and outer 



(secundine). 



7. The small passage (micropyle) leading through 

 the coats down to the nucleus. 



S. In some specimens, a large cavity (the embryo- 

 sac] will be seen in the nucleus just opposite 

 the micropyle. In the embryo-sac may be 

 seen some small granular cells (the embryo- 

 cell and endosperm cells}. 



62 



