216 



BOTANT. 



chlorophyll-bearing, none being in any wise parasitic. 

 Common examples are the pines, spruces, firs, etc. 



461. The general structure of the reproductive organs 



Fig. 120. — A cluster of staminate cones or flowers. ^, of a Pine (Pinus sylves- 

 tris), with a detached stamen. Natural size. B, showing the two pollen-sacs. 

 Considerably magnified. 



may be understood from a study of those of the pines. 

 The pollen-bearing flowers — staminate flowers, as they are 



Fig. 121.— Pollen-cells of Glymnospenns. A, of a Cycad; y, rudimentary first 

 stage (prothalimm), one pollen-cell germinating. B, pollen-cells of a Hne, side 

 and top views, showmg bladder-like enlargements of outer cell-wall bl- the 

 rudimentary prothallium is shown here also. Much magpifled. 



