Befruchtung. '].T\ 



Taxodium was the first to describe a case in which the cytoplasm of 

 the male nucleus surrounds the fusion-nucleus and plays an important 

 part in the formation of the embryo. In this plant the male cytoplasm 

 is packed with starch. A similar case has recently been recorded by 

 Lawson for Cryptomeria. Although Jaeger does not refer to it in 

 Taxus, two of his figures (pl. XVII, fig. 38, 39) distinctly suggest that 

 the same thing takes place in this genus. I have observed the contact 

 of the male and female nucleus in seven archegonia of Torreya cali- 

 fornica, and always without exception a layer of specially dense cyto- 

 plasm has been found to occur on the side of the two nuclei from which 

 the male nucleus has approached. It is thickest opposite the middle of 

 the male nucleus, and exactly recalls the texture of the body-cell proto 

 plasm. My Figs. 99, 19 — 21 should be compared with Coker's fig. 103. 

 I think it is safe to assume that this cytoplasm was brought in by the 

 male nucleus." 



Nachdem der Zygotenkern sich zweimal geteilt hat und also 4 Kerne 

 vorhanden sind, fängt die Zellwandbildung schon an, und es wurde also 

 keine Spur der ausgedehnten freien Zellbildung gefunden, welche für 

 Taxus und Cepimlotaxus beschrieben worden ist und als ein primitives 

 Merkmal betrachtet wird. Die Zahl der Chromosomen beträgt anscheinend 

 in der weiblichen x-Generation 8. 



Miss Robertson schließt: 



„I begau the study of the spore development and sexual organs 

 of T. californica not unprepared to find at any rate some Oycad-YikQ 

 traits, but this expectation has scarcely been realised. If I have counted 

 the chromosomes correctly the number agrees with Ceratoxamia (and 

 Taxus) and differs from that usually found in Conifers.'''' 



Daß dies aber wenig betreffs der Verwandtschaft aussagt, mag durch 

 untenstehende, von Coulter und Chamberlain entliehene Tabelle der 

 «Chromosomeuzahlen bei verschiedenen Liliaceen illustriert werden: 



Convallaria majalis in einem Falle 16?, im anderen 18 

 Trillium (2 Arten) 6 



Leucojum vernum 12 



Innerhalb der Familie schwankt die Zahl also von 6 — 24 Chromo- 

 somen in der x-Generation, von 12 — 48 in der 2 x-Generation. 



Miss Robertson fährt fort : „but in no other point have I succeeded 

 in recognising any additional evidence for the relationship of Torreya 

 with the Cycads — a relationship which is clearly suggested by the 

 structure of the seed and seedling." 



Wir haben aber oben schon gesehen, daß in diesem Satz der Nach- 

 druck auf das Wort „suggested" fallen muß. 



