108 MORPHOLOGY OF SPERMATOPHYTES 



species. Of these seventy-one species, forty belong to the single 

 genus Podocarpus, as characteristic of the south temperate re- 

 gions as Pinus is of the north temperates. At least two series 

 of Taxaceae are evident, the Podocarpeae and the Taxeae. In 

 the former, containing fifty-four species, the ovules are appar- 

 ently foliar and the pollen grains are winged ; while in the lat- 

 ter, containing seventeen species, the ovules are apparently 

 cauline and the pollen grains are wingless. 



The Pinaceae display at least four distinct series of forms, in 

 three of which (Araucarieae, Abieteae, and Taxodieae) the spiral 

 leaf arrangement prevails throughout, in bracts and sporophylls 

 as well as in the ordinary leaves; and in one (Cupresseae) the 

 leaf arrangement is cyclic throughout. The Araucarieae, con- 

 taining about fourteen species, and prominent in the southern 

 hemisphere, have almost completely coalescent bract and scale, 

 solitary ovules, and free pendulous pollen sacs. The Abieteae, 

 containing about one hundred and twenty-two species and form- 

 ing the prominent coniferous forest display of the northern 

 hemisphere, have almost completely distinct bract and scale, 

 winged pollen, and needle leaves. The Taxodieae, containing 

 about twelve species, have almost completely coalescent bract 

 and scale, and wingless pollen. The Cupresseae, containing 

 seventy-eight species, are distinguished from the other groups 

 of Pinaceae by the cyclic character, and may have the strobili 

 ripening hard or fleshy (as in Juniperus). 



The morphological evidence seems to point to the belief that 

 the Taxaceae represent the more primitive forms of Conifers, 

 and that among the more recent Pinaceae the Abieteae, and 

 notably the genus Pinus, stand for the most specialized forms. 



A tabulated statement of the classification outlined above is 

 as follows, the numbers following each genus indicating the 

 approximate number of recognized species it contains : 



A. TAXACEAE 

 I. Podocarpeae 



1. Saxogothaea 1 



2. Microcachrys 1 



3. Podocarpus 40 



4. Dacrydium 12 



II. Taxeae 



5. Phyllocladus 3 



6. Cephalotaxus 4 



7. Torreya 4 



8. Taxus . . 6 



