5°S 



BOTANICAL GAZETTE 



[DECEMBER 



nature of the storage material led to the following results. Fresh 

 sections after having been boiled in Fehling's solution showed many 

 red-brown cells (fig. 8). The sections were then washed in water 

 and treated with a solution of iodine in potassium iodide. These 



cc 



a 



sugar cells " remained red-brown, while the others gave a strong 

 starch reaction. The sections were again washed in water and 

 then treated with potassium bichromate, and the reddish cells 



turned very dark brown. 

 Fig. 9 shows a portion of a 

 section at this stage. Tested 

 with ferric chloride these 

 sugar cells' ' gave the charac- 

 teristic tannin reaction. 

 cc Trimble (33) states that 



glucose is frequently present 

 with tannin, and also that 

 tannin will reduce Fehling's 

 solution; consequently the 

 reactions described above 

 may be due to tannin and 

 glucose or to tannin alone. 

 Trimble also found that in 

 the rhizome of Acorus Cala- 



1-iG. ii-Scirpus valid us: longitudinal h tannin „ beari ng cells 



were quite distinct from the 



section of stem: d, diaphragm extending 

 into partition; par, ordinary, polygonal, 

 partition cells; cc, partition cells elongated starch-bearing cells, 

 for conductive function; circles in cells indi- 

 cate cut arms; stippling to distinguish cells 

 from spaces; Xno. 



When fresh specimens of 

 Scirpus validus were tested 

 with vanillin and concentra- 



ted HO, according to the method described by Hartwich and 

 Wixckel (16), it was found that numerous cells turned ruby red. 

 This reaction showed the presence of phloroglucin or some 

 related tannoid. The reaction did not take place with HC1 

 alone, therefore the necessary aldehyde was not present in the 



cell - 



Washing the sections 



in water caused the red color to 



disappear, and subsequent treatment with K 2 Cr 2 7 brought out 

 strongly the tannin reaction. This took place at once, instead of 

 slowly, as before the phloroglucin test. 



