PAPERS OX BIOLOGY AND AGRICULTURE 



93 



cotyledons that both are soon practically of the same 

 size (Figs. 7, 8). 



Desmogen strands show distinctly in a seedling hav- 

 ing cotyledons 15 mm. in length with an epicotyl 4 mm. 

 in length (Fig. 9). Phloem and xylem are not distinctly 

 differentiated in the strands; but they can be traced 

 easily. There are four root strands and one strand to 

 each cotyledon. The latter forms three desmogen 



~ f-^csst 



Fig. 9. 



strands. The first and second leaves show early traces 

 of similar strands. A single strand shows on each side 

 of the epicotyl. The primary root is present, but no ad- 

 ventitious roots. 



A slightly older embryo proved most helpful. Both 

 longitudinal and transverse sections were made. A re- 

 construction of the arrangement of the vascular bundles 

 was made from the transverse serial sections bv means 



