12 GRACE E. COOLEY ON 



1. Its easy solubility with hot, \V(3ak, miaei'al acids; the hemicellulose of Schulze. 



2. Its deep brown color with iodine in potassium iodide, with the exception of 

 Paris, Trillium, and Colchicum seeds. 



3. Its behavior toward chloroiodide of zinc as toward iodine in potassium iodide 

 solutions. 



4. Its resistance to the action of boiling water; exception, /r^N pKeuddconis and 

 unripe seeds of Paris. 



5. The slight coloring with haematoxylin and methyl violet. 



6. Intense coloring after long exposure to congo-red. 



7. Violet-blue in many cases with sulphuric acid after iodine. 



In the above particulars, it is to be distinguished from ordinary cellulose. 



8. The solubility in cuprammonia. 



9. Behavior towards caustic alkalies. 



These last two characteristics it shares with ordinary cellulose, as in cotton-fibers, 

 young shoots, etc. In general the reaction of the reserve cellulose in the presence of 

 microchemical tests is fairly uniform, but thei^e are some exceptions. 



The most noticeable of these are : — 



1. The reactions with weak, watery solutions of iodine, where the range is from 

 blue and violet to bi'own, or the walls remain colorless. 



2. The swelling of the walls of the endosperm cells of Iria pseudacorus and Pai'is 

 with boiling water. 



3. The exce2)tions to the action of sulphuric acid after iodine, as in Tulipa. 



4. The different lengths of time required to dissolve the reserve cellulose in the 

 presence of weak acids and cuprammonia. 



5. The reserve of Paris is exceptional in the following particulars : — 

 a. It swells considerably with water. 



h. It does not dissolve in cuprammonia. 



c. It is colorless with iodine, while Colchicum is faintlj' j-ellow. 



d. It occurs in connection with starch as a reserve substance. 



Trillium ovatum agrees with Paris in the three particulars investigated, and it is 

 probable that it will be found insoluble in cuprammonia. 



These facts seem to point to the following conclusions, with regard to reserve 

 cellulose in Liliaceae. 



