CONIFERS. 519 



opening left is that of the micropyle which faces the axis of the cone ; in Cun- 

 ninghamia there are three ovules, in Arihrotaxis from three to five, in Sequoia 

 from five to seven, in Sciadopitys as many as seven or eight on one scale, and 

 their micropyle here also faces the axis of the cone. In Dairimara the scale 

 bears, according to Endlicher ^ only one ovule which, like those of Sequoia and 

 Sciadopitys, are inserted near the apex and hangs down free^. 



^ [Van Tieghem has been led by studying the distribution of the bundles in the different parts of 

 the female bud of Coniferte to the opinion — different from that expressed by Sachs— that the female 

 flower throughout this group of plants is in every case constructed after a single fundamental type 

 which has undergone various secondary modifications. He has given in a note to his French trans- 

 lation of the present work the following abstract of the conclusions which are worked out in greater 

 detail in his paper already cited in the Annales des Sciences Naturelles. 



Neither the axis of the female bud nor its leaves or bracts of the first order ever bear ovules. It 

 is always upon structures arising from the axils of these bracts that the ovules make their appearance. 

 This establishes a fundamental distinction between Cycadese and Coniferse. In the former group it 

 is always the leaves of the female bud of the first order that produce the ovules directly. While 

 therefore we may regard the female bud in Cycadese as well as the male as contributing a single 

 flower, this does not hold good in the case of Coniferse. We may if we please regard the male bud 

 of Coniferse as a single flower, but the female bud is an inflorescence. The structure which bears 

 the ovule in Coniferse is always a foliar organ — the first and only leaf of an axis which undergoes no 

 further development. This leaf, which is more or less largely developed beyond the circumscription 

 of the ovule or ovules which it bears, is an open carpel and in itself constitutes the whole female 

 flower. It is always inverted, that is to say, it arises upon the suppressed axis which bears it with 

 its ventral face opposite to and united with the ventral face of the primary bract. When the ovules 

 do not terminate the carpel, it is upon its structurally dorsal — but in respect of position upper — face 

 that they arise, just as it is upon its structurally dorsal — but in respect of position lower — face that 

 the pollen-sacs arise upon ths stamen. 



This is the general type. It remains to consider the principal secondary modifications which are 

 superinduced upon it in the different genera. 



The axillary branch, which is reduced to its first leaf, is most frequently of the first generation 

 in respect to the axis of the female bud ; but it is also sometimes of the second (Tnxus) and may 

 even be of the third order {Torreya). The carpel itself is either entirely distinct from the parent 

 bract (the Pinese, Taxinese) or the two leaves are united together by their ventral surfaces and are 

 only separate towards their summit (Cupressinese, Sequoiese, Araucariese). This difference merely 

 depends upon a different localisation of the intercalary growth of the two leaves ; it is a difference 

 the same in kind as that which separates a dialypetalous corolla from a gamopetalous one. Whether 

 free or united with the bract, the carpellary leaf bears its ovules sometimes towards its base 

 (Cupressineoe), sometimes towards its middle (Pinese), sometimes towards its summit (Araucariese) ; 

 each represents a lobe, more or less developed, of the dorsal face of the carpel. 



In the TaxinecE the ovules terminate the carpellary leaf; they result in this case from the trans- 

 formation of its who.e entire limb, whether each half of the limb forms an ovule {Salisburia, Cepha- 

 lotaxus), or whether the entire limb has only produced a single one {Podocarpus, Phyllocladns, Taxris, 

 Torreya, &c.). In this case it is evidently only the petiole of the ovuliferous leaf which represents the 

 carpel ; if the petiole is long (Salisburia) the carpel is obviously developed ; but if it remains very 

 short {Cephalotaxus, Podocarpus, Phyllocladns, Taxus, Torreya, &c.) the carpel is alrnost absent — in 

 otl.er words, the carpellary leaf is reduced to a sessile limb completely converted into a single ovule 

 {Podocarpus',^ Taxus, &e.) or into two ovules {Cephalotaxus). The number of the ovules which each 

 carpellary leaf bears, as well as the number of carpellary leaves themselves, that is to say, of the 

 female flowers which enter into the composition of the inflorescence, both vary, and may even be 

 simultaneously reduced to unity, which is the ordinary case in Taxus.] 



2 [For a review of the literature of the question whether the ovules of Coniferx are really naked 

 or whether there is a true ovary, see Eichler, ' Sind die Coniferen gymnosperm oder nicht ? ' in ' Flora' 

 for 1873, translated in Trans. Bot. Soc. Edin. 1873, PP- 535-541- ^^- Eichler here, in opposition to 

 the contrary view of Strasburger, sums up the whole argument strongly in favour of the opinion that 



