PAPERS OX BIOLOGY AND AGRICULTURE 



95 



EPICOTYL ANATOMY (FIG. 13) 



The following is the arrangement of the fibro-vascular 

 bundles in the lower part of the epicotyl. In the center 

 are four very prominent central bundles. Surrounding 

 these are twelve smaller bundles, roughly describing a 

 circle. The cotyledons were cut off between these bundles 

 and the peripheral bundles. The latter are of course 

 cotyledonary bundles, not epicotyl bundles. This ar- 

 rangement continues for a considerable distance, but is 

 disturbed at the level where the adventitious roots are 

 given off. Six were formed in the seedling from which 

 the model was made. They are the first permanent roots, 

 and arise from an almost complete ring formed by the 

 central bundles. The first leaf is supplied by strands 



Fig. 14 



which connect with one of the four central bundles, by 

 peripheral strands, and by fusion strands connected with 

 these two types. However, the suceeding leaves are sup- 

 plied by fusion strands from all the epicotyl bundles. 

 The arrangement of three desmogen strands to a leaf 

 shown so clearly in the younger seedling has given place 

 to a fusion type of structure. At this stage the petiole 

 of the first leaf does not show fusion of strands. The 

 adult leaf of Nelumbo lutea was cleared by immersion 

 in equal parts of hot absolute alcohol and glacial acetic 

 acid followed by immersion in clove oil and later by im- 

 mersion in xylol. 



