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PLANT-LIFE 



numerous scales are arranged spirally round the axis; 

 these conspicuous scales are outgrowths from the upper 

 surfaces of smaller, carpellary scales, which precede 

 them in appearance. The larger scales are called 

 cvuliferous, because they bear naked ovules as shown 

 in Fig. 60, C. 



The male flowers produce a vast quantity of pollen, 

 which is very light and easily carried by the gentlest 



Fig. 60. — Spruce Fir (Picea excelsa). 



A, Twig with female cone; B, twig with male cones; C, scale detached from 

 female cone (A) bearing two winged ovules (s, s). 



breeze of wind. As the Firs are entirely dependent 

 upon wind for transportation of pollen, they must needs 

 produce pollen in quantity in order that some of it 

 may chance to drift to the female flowers. The pollen 

 of the Firs is exceedingly light in proportion to its 

 surface, and each grain is laterally expanded, the ex- 

 pansions being comparable with wings. It is in the 

 month of May that pollination takes place, and in 

 order that the pollen may reach the ovules with greater 



