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abundance in the cambium layer, and the largest percentage 

 in the buds. In these hist places, when the buds are mature, 

 the albuminoids make up a large part of the cell contents, to 

 the exclusion of the starch. All the varieties studied exhib- 

 ited the albuminoids as brick-red particles when treated with 

 the Millon test, a nitrate of silver compound, described else- 

 where. On account of the conspicuous color the presence of 

 the protoplasmic compounds is easily demonstrated. When 

 the tip of a twig was still soft, spongy and without rigidity 

 from a failure of the pith to lignify, there was only a feeble 

 response. Protoplasmic matter was present, but so scattered 



* The methods observed in the niicro-phytochemical study of these car- 

 bohydrates will receive separate treatment at the close of the paper. 



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there can be no very great toughness. Contrariwise, brittle^ 

 ness characterizes the upper portion of a well-matured twig, 

 and for two or three inches below the terminal bud it will 

 often snap, almost like a pipe-stem^ when sufficient side 



pressure is applied. 



Su£^a7'S. — Tests for other carbohydrates were made, princi- 

 pally the various sorts of sugars.* Grape sugar was gener- 

 ally present in variable quantities in all terminal buds. Cane • 

 sugar and dextrine were likewise present in most cases, but in ^ 

 small quantities. Grape sugar was most evident near the 

 growing points, and cane sugar, if it appeared at all, was in 

 the fine, unlignified tissue at the base of the bud. In view 

 of the fact that starch is readily changed into sugar within 

 the plant, under conditions similar at least to those sur- 

 rounding the twigs when gathered for testing, it follows that 

 sugar, w^hich in this connection may be considered as another 

 term for soluble starch, would be expected, and in variable 

 quantities. Twigs gathered directly from trees also showed' 

 these sugars in small amounts. 



Albuminoids or Proteids, — This group of complex and very 

 variable substances does not readily admit of separation into 

 . individual sorts, and is therefore treated as a whole. Proteids 

 are present in all living parts of ligneous plants, and are most 

 abundant near the points of greatest vital activity. In the 

 apple, for example, there is little or no albumen in the pith 

 at the base of an old twig, very little in the wood zone, an 





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