CONIFERALES 



•317 



two figures show a sperm almost as highly organized as in the cycads 

 and Ginkgo. Whether each sperm is formed inside a sperm mother- 

 cell, as in the cycads, or arises from the division of the body cell, so 



Fig. 315.— Body cells and sperms in the Taxodiaceae: A, Taxodium distichum, the 

 two highly organized sperm cells, with the stalk and tube nuclei in advance; X540; after 

 Coker;'-!' B-D, Cunninghaniia sinensis: B, pollen grain with generative cell and tube 

 cell (no prothallial cells) ; C, body cell and stalk and tube nuclei; X430; after Miyake-'"" 

 E, F, Cryptomeria japonica: E, body cell and stalk and tube cells; F, the two sperms; 

 X666; after Lawson.3« 



