Morphologie der Reproduktionsorgaue. 331 



Miss Sykes. sich auch auf den Verg-leich mit Cardiocarpus stützend, 

 daß das sogenannte Perigon der weiblichen Welwitschia-^XvLie, in der 

 Tat ein äußeres Integument des Ovulums ist. 



Homologien zwischen den d und $ Blüten. 



Im Zentrum beider Blüten findet sich ein, wenn auch bei den männ- 

 lichen reduziertes Ovulum. Ob das Integument dieses reduzierten Ovu- 

 lums der S Blüte dem äußeren oder dem inneren Integument des Ovu- 

 lums der $ Blüte entspricht, läßt sich nicht entscheiden. 



Die S Blüte betrachtete Strasburger als einen amphisporangiaten 

 Strobilus, die weibliche kann auch von Anfang an unisexuell gewesen sein. 



Miss Sykes meint jedoch, daß der ganze Welwitschia-Kegel dem 

 Bennettites-&tYobi\n& homolog ist, indem sie „some at auy rate of the 

 intraseminal scales in Bemiettites regards as the equivalent of the bracts 

 of Wchrltschia. The ovule (Bemiettites) would thus be homologous with 

 the female Üower of Welwitschia^^. 



Sie betrachtet also das Periauth der $ Welwitsckia-Blüte als ein 

 Integument, etwa wie Pearson als das Homologon des „basal husk" von 

 Bemiettites. Weiter aber betrachtet sie die $ Blüte von Welwitschia 

 -}- deren Stützbraktee als das Homologon des CV/cac^ee;^ -Sporophylls! 

 Ich schreibe hier wörtlich ab, was sie sagt über die 



Comparison between Welwitschia and the Cycads. 



A füll discussion of the questions involved in this comparison cannot 

 be entered into until the adult and seedling anatomy of Welwitschia has 

 been further studied, but several points of striking resemblance between 

 the anatomy of the Cones of Cycads and Wehvüschia have already been 

 described. The resemblance, carried as it is into minute details, such 

 as the method of origin of the double bundles supplying the ovuliferous 

 scales of the one and the Üowers of the other, the presence of centri- 

 petal wood and inversely orientated bundles in conuection with the 

 bundles of the peduncles, and the occasional development of normal 

 concentric bundles in various regions, makes it almost impossible that 

 there should not be some relation between these forms. 



Yet in the Cycads the cone, or so called flower, consists of an axis 

 bearing scales on which the ovules and microsporangia occur, being 

 therefore foliar in origin, while in Welwitschia a collection of cones 

 forms an intlorescence, and each cone consists of an axis bearing scales 

 with axillary ovules and microsporangia on stalks. 



In Welwitschia it is difficult not to regard the ovule as cauline (the 

 occurence of anomalous macrospores in the axis of the female cone is 

 an argument for the cauline nature of the ovule), the morphological 

 equivalent of an axillary bud, as probably also in the Cordaitales. Yet it 

 seems possible that in view of other resemblances this difference in the 

 Position of the ovule may be regarded as secondary and each braet 

 with its axillary ovule in the female cone of Welwitschia may be 

 homologised with an ovuliferous scale of Dioo?i. In the former case 

 as in the latter both scale and ovule have a common vascular supply; 

 in Welwitschia it usually happens, that the bündle supplying the bract 

 becomes separated early, but as in the Cycads it arises iVom the same 



