286 



MORPHOLOGY OF GYMNOSPERMS 



9 





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332 







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333 



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336 



335 



337 



Figs. 332-337.— Fertilization in Pimis: fig. 332, P. siheslris, the sperm nucleus 

 entering the egg nucleus, June 19; X135; after Blackman (46); fig. 333, P. Laricio, 

 the chromatin of the sperm and egg nuclei in the spirem stage within the limits of the 

 egg nucleus; Xsoo; after Chamberlain (51); figs. 334-337, P- Strobus; fig. 334, a 

 somewhat later stage than that shown in fig. 333; fig. 335, the spirems of the egg and 

 sperm nuclei after segmentation; fig. 336, the two spirems after segmentation; the 

 two halves of the spindle seem to indicate the paternal and maternal parts of the 

 mitotic figure; fig. 337, longitudinal section, showing the orientation of chromosomes 

 at the nuclear plate, the egg and sperm chromosomes no longer distinguishable; 

 X315; after Miss Ferguson (87). 



