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THE AMERICAN NATURALIST [Vol. XLIII 



Perhaps nowhere is the advantage of morphological 

 bookkeeping by double entry more clearly illustrated than 

 in the case of the conifers. Forming with the other living 

 gymnospermous species a restricted but illustrious ' 'four 

 hundred," they have quite held their own in botanical 

 interest, in spite of the overwhelming numbers and im- 

 portance of the modern mob of angiosperms. The older 

 and entirely superficial morphology, led to the conclusion 

 that simple forms and structures are more primitive. On 

 this basis the conclusion was reached that those simple 

 and coneless conifers, the Taxineje or yews, are the oldest 

 and that the pines or Abietinete, with their very compli- 

 cated cone-structures, are most modern. It has, moreover, 

 been inferred that the coniferous tribes represent a series 

 of progression beginning with the yews and ending with 

 the pines. The microscopic study of the gametophytes 

 began the disintegration of this system. The discovery 

 of zoidogamous fertilization in Ginkgo, which in Engler 

 and Prantl's Natiirliche Pflanzenfamilien, you will find 

 included with the yews, made it at once apparent that this 

 remarkable genus, sole survivor of an abundant stock, 

 once flourishing through the entire northern hemisphere, 

 could not be included under the Taxinese, or link the latter 

 with the still more ancient Cordaitales, confined to the 

 Paleozoic. Thus deprived of the reputation of an illus- 

 trious ancestry, the yews have since been disrespectfully 

 kicked up the phylogenetic stairs by the younger genera- 

 tion of gametic morphologists. A corresponding but re- 

 versed process has in the meantime taken place at the 

 other end of the coniferous series. It has been shown by 

 the gametophytic morphologists, that the sexual genera- 

 tions of the pine tribe are more complicated, and for that 

 reason more primitive in the reduced members of the 

 alternation, than any other conifers, characteristically 

 found in the northern hemisphere. From the sporo- 

 phytic side it has been shown that the cone-structure of 

 Pinus affords an anatomical explanation of the strobilar 

 organization of the other tribes of conifers on the basis 



