88 HISTOLOGY OF ANGIOSPERM STEM, ROOT, ETC. 



(e) Examine with a lens the bundles ; the hard middle 

 portion (wood) of each bundle shows the large open 



(/) Place a living piece of Marrow shoot with its cut 

 end in red ink and when the red colour has appeared in 

 the leaves cut the stem and note that the ink has passed 

 through and stained these wood vessels. 



(</) Cut across a piece of fresh living stem with a dry 

 knife or razor, and note the juice which oozes out of the 



Fig. 23. Transverse Section of Stem of Vegetable Marrow. 



soft outer and inner portions (phloem) of each bundle ; 

 collect some of this juice on a slide and test it for 

 (i) sugar with Fehling's solution ; (ii) starch with 

 iodine; (iii) proteids with Millon's reagent, etc. 



100. T. S. Marrow Stem (Figs. 23, 24). Cut 

 transverse sections of the stem ; mount some at once in 

 glycerine, others after treatment with one of the follow- 

 ing reagents : iodine, chlor- zinc-iodine, aniline sulphate, 

 Millon's reagent. Also test a fairly thick section with 

 Fehling's solution or boil in Fehling a short piece of 



