

1 



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1920] HAINING—GNETUM 443 



There is certainly none in this position in the other species studied 

 bv the writer. 



Buchholz concludes that cleavage polyembryony is a primitive 

 condition in the Abietineae. It is therefore interesting to note 

 that certain species of Gnetum retain this condition. There is no 

 fusion of suspensors resulting in a reduction of the number of 

 embryos, such as Buchholz finds in the higher Abietineae and 

 regards as an evolutionary development. The occasional formation 



mbr\ 



mental significance. 



Summary 



1. The proembryo of G. funiculare 



from 



2. Cross-walls and nuclei are formed in these tubes, associated 

 with the branches. 



3. In G. sp. 15, G. sp. 29, and G. sp. 59 the suspensors form a 

 coiled rope in a cavity in the endosperm ; while in G. funiculare, as 

 in G. Gnemon, they branch widely through the endosperm. 



4. In the ripe seeds a peculiar cell is present at the end of the 



primary suspensor. 



5. When germination begins in G. sp. 15, G. sp. 29, and G. sp. 59, 

 a very long multicellular secondary suspensor is formed by division 

 of this cell at the tip of the tube. In G. Gnemon no such body 

 appears. 



6. The development of cotyledons, root tip, and "foot" at the 

 end of the secondary suspensor is described. 



7. Polyembryony is the rule. Several of the primary suspensors 

 usually form secondary suspensors. In some cases these are closely 

 associated and develop equally for some time. In other cases one 

 of the suspensors wins out at an early stage, and the others separate 

 and become stunted. Occasionally the tip of the secondary sus- 

 pensor divides into a number of branches. Branches from the 

 side of a secondary suspensor are sometimes observed. 



8. Except in the reduction of the amount of free nuclear division 

 in all species and in the suspensors in G. Gnemon the development 

 is gymnospermic. 



