CHAPTER XII 

 CONIFEROPHYTES— CONIFERALES— Co«//;H<ef/ 



THE SPOROPHYTE — REPRODUCTIVE 



The cone is the most characteristic feature of the order and the 

 one to which it owes its name. The staminate strobih are conehke 

 throughout, but the Taxares (Taxads and Podocarps) have some- 

 times been described as conifers without cones because the female 

 strobili do not look like the familiar cones of the other families. 



The separation of the sexes shows all conditions from bisporan- 

 giate strobili to monoecism and to a complete separation in typical 

 dioecism. The monoecious condition is dominant. Bisporangiate 

 strobili occur only as occasional abnormalities. 



The Abietaceae and Taxodiaceae are uniformly monoecious. In 

 the Cupressaceae, Fitzroya, Diselma, and Arceuthos are dioecious, 

 and Juniperus communis, usually dioecious, occasionally bears both 

 male and female strobili on the same plant; but, in such cases, either 

 the male or the female is dominant, recalling the condition in Canna- 

 bis saliva and some other angiosperms, which are evidently in transi- 

 tion from monoecism to complete dioecism. The other genera of Cu- 

 pressaceae are monoecious. The Araucariaceae are dominantly dioe- 

 cious, but Agathis australis and Araucaria hidwilli are monoecious. 

 The Taxaceae are dioecious, except in occasional individual cases. 

 In the Podocarpaceae the dominant genus, Podocarpus, is dioecious, 

 although there have been reports — not very convincing — of occa- 

 sional monoecism. Some species of Phyllocladus and Dacrydium are 

 monoecious. 



The survey shows that the great majority of the genera are monoe- 

 cious, a much smaller number having attained the dioecious condi- 

 tion. In the plant kingdom, from the algae to the highest dicotyls, 

 the course of evolution shows a progressive separation of the sexes, 

 with such intermediates and mixtures that the dioecious condition 

 is evidently the goal. As far as this single feature is concerned, the 



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