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EDWARD C. JEFFREY OX 



Sciadopitys is almost a demonstration of its accuracy. The hypothesis which explains the 

 ovuliferous scale of the Abietineae as a reduced and modified short shoot ( brachy blast ) , is 

 likewise in harmony with teratologieal evidence, for in the so called proliferous cones of 

 certain Abietineae, the ovuliferous scale becomes more or less completely transformed into 

 a leafy bud and the subtending bract into an ordinary vegetative leaf. It is a curious and 

 interesting fact, which does not seem to have been properly considered in regard to its 

 bearing on the phylogeny of the Coniferales, that cases of proliferous female cones are 

 confined, in the present state of our knowledge, to the Abietineae and the Taxodineae 

 (Penzig, Pfianzenteratologie, 1894, vol. 2, p. 485-514). To those who accept the brachy- 

 blastic theory of the uature of the ovuliferous apparatus in the Coniferales, this state of 

 affairs must appear weighty evidence in favor of the view that the Abietineae, and the 

 Taxodineae as well, are somewhat primitive orders of the group, for there would naturally 

 be the greatest tendency to reversion and the clearest anatomical evidence of the shoot 

 value of the ovuliferous scale iu the orders which are nearest to the ancestral stock. 



In the case of the Taxodineae, the scales of the female cone are not superposed in 

 pairs but consist of single, generally more or less thickened ovule-bearing organs, in 

 which there is present a double system of bundles consisting of an upper and a lower 

 series oriented in opposite directions, as are those of the separate superposed scales of the 

 Abietineae. The generally accepted description of the state of affairs in the cone scales 

 of the Taxodineae, is that there is a fusion of the ovuliferous and sterile bracts. It is 

 scarcely logical to speak of organs as being " fused " unless they were originally sepa- 

 rate. The view that they were primitively separate, superposed scales in the ancestral 

 stock of the Taxodineae is strengthened by a consideration of the anatomical facts in 

 the case of the genus Sequoia ; for it is not easy to conceive that the series of massive 

 bundles near the upper surface of the cone scale in this genus is arising de novo for the 

 benefit of the reproductive organs, since the ovular bundles are extremely small and 

 quite out of all proportion to the fibro vascular strands of the upper system from which 

 they take their origin. The more reasonable explanation seems to be that the thick, 

 single scale which bears the ovules in the case of most of the Taxodineae, is made up of 

 a fusion of two separate scales which existed in a more primitive group, probably the 

 Abietineae or their parent stock. This view of the matter receives further support from 

 the peculiar manner of the occurrence of resin ducts in the woody tissues of living and 

 fossil Sequoias. 



It would be anticipating unduly the results to be recorded in subsequent memoirs on 

 the Coniferales, to express more than a provisional opinion as to the position of the genus 

 Sequoia but this much may be safely stated. The anatomy of living and fossil species of 

 Sequoia goes to show that the genus has come from a stock possessing ligneous resin 



