Befruchtung. 171 



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

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

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

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

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

 Taxus, two of his fig-ures (pl. XVII, fig". 38, 39) distiuctly sugg-est that 

 the same thiug takes place in this geuus. 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 textuie 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 Cephalotaxus 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 began the study of the spore developmeut and sexual organs 

 of T. californica not unprepared to find at any rate some Cycad -liko, 

 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 

 Chromosomenzahlen bei verschiedenen Lüiaceen illustriert werden: 



in der x-Generation 



Funkia Sieboldiana 24 



Ällium (3 Arten) 8 



Lilium (7 Arten) 12 



FritiUaria (2 Arten) 12 



Tulipa Gesne7-ia7ia 8 



Erijthro7iium americanum 12 



Galtonia candicans 8 



Scilla (2 Arten) 8 



Muscari neglectum 24 



Convallaria majalis in einem Falle 16?, im anderen 18 



Trillium (2 Arten) 6 



Leucojum verninn 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 Cyeads — 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. 



