542 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1914. 
Certain teguments taken from castor beans had given off in darkness 
1.61 per cent of carbon dioxide and had reduced the quantity of 
oxygen to 15 per cent while the separated embryos from which they 
had been taken, placed with their endosperm in the same conditions, 
had not changed their atmosphere at all. If the gaseous exchanges 
of these seeds protected by their teguments had been interpreted as 
true respiration, one would have arrived at the paradoxical conclu- 
sion that the tezuments composed of dead cells respired, while the 
embryos with their endosperm ready to germinate, having neither 
absorbed nor thrown off the least particle of gas, were dead. 
The results obtained with several kinds of decorticated seeds, such 
as those of peas, beans, and lupine, in their natural state of desic- 
cation, that is, still containing a certain quantity of water, convinced 
me that after a certain time in darkness they absorb traces of oxygen 
and throw off traces of carbon dioxide. There must therefore be in 
the embryos of those seeds which were not protected by their tegu- 
ments and were in their natural state of desiccation extremely slight 
gaseous exchanges. 
IV. THE NATURE OF THE GASEOUS EXCHANGES IN SEEDS. 
But are these gaseous exchanges that are indicated in the case of 
the decorticated seeds in their state of natural desiccation really 
caused by a true respiration, the result of a kind of relaxed life for 
which the oxygen of the air is absolutely necessary? To find this 
out, I rendered the respiration of the embryo impossible by depriving 
it by means of a vacuum of its internal atmosphere confined in the 
intercellular spaces and in the cells themselves which intercommuni- 
cate so readily through the punctures of their walls. The embryo 
was then placed for a greater or less time in contact with irrespirable 
media. Treated thus, peas with their teguments perforated, and 
deprived of their internal atmosphere, remained a year under the 
mercury and grew perfectly after the experiments. Seeds of beans, 
peas, castor beans, and wheat after decortication were kept in dark- 
ness in an atmosphere of nitrogen without giving off any trace of CO, 
and without losing their power of germination. 
Other seeds of lupine, lucern, peas, clover, mustard, pumpkin, buck- 
wheat, and pine, and grains of wheat and oats, after perforation of 
their tegument were kept for eleven months in pure and dry carbon 
dioxide without suffering any injury. Finally, desiccated seeds of gar- 
den cress, lucern, and peas, and grains of wheat with the tegument 
perforated, were inclosed for two years in vials in which a nearly com- 
plete vacuum had been obtained, without injury to their germinative 
power. 
These are new results, all agreeing, which are opposed to those 
classic experiments on which dependence is still placed to show the 
