4i 8 Fry. — On Aggregations of Proteid, &c. 
one of which had been kept in the dark for some days, the 
other in the light. As was to be expected, the etiolated leaf 
had used up much of its reserve proteid. 
I next investigated the effect of light on the formation of 
proteid by imitating exactly Sachs’ macroscopic starch-test, 
except that I substituted Loew’s ferrocyanide-test for treat- 
ment with iodine. In no case did I find that light had any 
effect on the quantity of proteid formed. 
These observations then tend to show that the proteid is 
used as reserve nitrogenous material, answering to starch 
among carbohydrates. It is noteworthy that the distribution 
in the stem of the cells containing proteid is similar to that 
of the irregular starch-sheath, cells containing proteid al- 
ternating with cells containing starch. In all physiological 
respects these proteid-containing cells resemble the ‘ Eiweiss- 
schlauche ’ of the Cruciferae described by Heinricher 1 , as also 
in many respects in their distribution. 
I may mention that I examined many species of the 
Euphorbiaceae and many latex-containing plants of other 
families, belonging to the genera Manihot , Hoya, Hevea , 
Oxypetalum , Ficus , Sapium , Pharmacosycea , without finding 
any such aggregation of reserve proteids. 
I ought to add that Euphorbia Bojeri y by some considered 
as a variety of E. splendens y is exactly similar to it as regards 
its accumulations of proteid. 
In conclusion I must thank Professor Vines and Mr. 
Gardiner for their helpful suggestions and advice in this 
investigation. 
1 E. Heinricher, Eiweissschlauche d. Cruciferen, Mitth. aus dem Bot. Inst, zu 
Graz, 1 886 . 
