STORAGE OF FOOD IN THE §EED 19 



Of what use -would it have been to the plant ? 



If the student wishes to perform this experiment at home for 

 himself, he should bear in mind the following. 



Caution. — Never handle benzine or ether near a flame or stove. 



A much simpler experiment to find oil in seeds may readily be 

 performed by the pupil at home. Put the material to be studied, 

 e.g., flaxseed meal, corn meal, wheat flour, cotton-seed meal, buck- 

 wheat flour, oatmeal, and so on, upon little labeled pieces of white 

 paper, one kind of floiu- or meal on each bit of paper. Place all the 

 papers, with their contents, on a perfectly clean plate, free from 

 cracks, or on a clean sheet of iron, and put this in an oven hot 

 enough nearly (but not quite) to scorch the paper. After half an 

 hour remove the plate from the oven, shake off the flour or meal 

 from each paper, and note the results, a more or less distinct grease 

 spot showing the presence of oil, or the absence of any stain showing 

 that there was little or no oil in the seed examined. 



24. Albuminous Substances. — Albuminous substances 

 or proteids occur in all seeds, though often only in small 

 quantities. They have nearly the same chemical composi- 

 tion as white of egg and the curd of milk among animal 

 substances, and are essential to the plant, since the living 

 and growing parts of all plants contain large quantities of 

 proteid material. 



Sometimes the albuminous constituents of the seed 

 occur in more or less regular grains (Fig. 8, Kl). But 

 much of the proteid material of seeds is not in any form 

 in which it can be recognized under the microscope. 

 One test for its presence is the peculiar smell which it 

 produces in burning. Hair, wool, feathers, leather, and 

 lean meat all produce a well-known sickening smell when 

 scorched or burned, and the similarity of the proteid 

 material in such seeds as the bean and pea to these sub- 

 stances is shown by the fact that scorching beans and 

 similar seeds give off the familiar smell of burnt feathers. 



