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284 



BOTANICAL GAZETTE 



[OCTOBER 



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five to one archegonia in a chamber. An exceptional case was noted 



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in which there were two archegonial chambers, each containing five 

 archegonia; also instances were noted in which no archegonia were 

 produced . 



In Ginkgoales the two equal sperms are discharged into an arche- 

 gonial chamber usually containing two archegonia, although occasion- 

 ally three may be present; one functional and one abortive archego- 

 nium are not infrequent. Here, as in cycads, conditions are favorable 

 for the retention of equality of sperms, at least for a very long time. 



In Coniferales the situation is variable. In Podocarpus coriacea^ 

 CoKER^° found unequal male nuclei. The long-necked archegonia 

 vary from six to ten and are separated from each other by one or more 



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layers of cells; and the jacket cells do not go to pieces at the time of 



fertilization. Since a pollen tube discharges its contents into a 



single archegonium, only one male nucleus can possibly function. 



In Taxus^^ and in Torreya'^ the male nuclei are unequal, and the 



In 



Torreya the usually solitary archegonium appears as soon as walls 

 are formed; even for a time after fertilization the walls are extremely 

 tenuous, but show no tendency to break down. The gametophyte 

 situation therefore closely resembles that in Ephedra. 



In Pinus the numerous archegonia are scattered as in Podocarpus, 



latter perhaps throws some light on the Ephedra situation. 



but differ in that each archegonium has an individual archegonial 

 chamber. The second male nucleus has no chance to function unless 

 it may occasionally fuse with the ventral nucleus. The male nuclei 

 are reported by Coulter' 3 to be equal in P. Banks lana; Chamber- 

 lain'-* reports them equal in P. Laricio; while in P. Strohus ]Miss 

 Ferguson' 5 reports them as unequal. An examination of Miss 



^<^ CoKER, W, C., Notes on the gametophytes and embryo of Podocarpus. Box. 

 Gazette 33:89-107. pis. $-7, 1902. 



Deutsch. Bot. Gesells. 11:196-201. pi. 12. 1893. 



" Coulter, John M., and Land, W. J. G., Gametophyt 

 reya taxijolia. Box. G-\zette 39:161-178. pis. A, 1-3. 1905. 



^3 Coulter, John M,, Notes on fertilization and embryo^ 

 Gazette 23:40-43. pi 6. 1897. 



Gymnospermen. Ber. 



Box 



4-6. 



Laricio. Box. Gazette 27: 268-280 



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IS FERGtfsox, Margaret C, Contribution to the knowledge of the life-history 

 of Pinus. Proc, Wash. Acad. Sci. 6:1-202. pis. 1-24. 1903. 



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