4 i 6 S toward- — On Endospermic Respiration in Certain Seeds. 
The view now generally accepted and recognized by Pfefifer (i), based 
apparently to a great extent on the work of Hansteen and Puriewitsch, is 
that the endosperm of the Gramineae is endowed with a capacity for 
auto-digestion ; provided that ample provision is made for the removal of 
the resulting metabolic products, and favourable conditions for germination 
are maintained. This view evidently implies that the endosperms possess 
vitality. 
Examination of the literature of the subject, however, shows that there 
is a lack of agreement on this question, different investigators having 
arrived at divergent conclusions in the interpretation of their experimental 
results. 
Gris (2), in a paper dealing with the physiology and anatomy of 
germination, makes mention of some changes observed by him in the cell- 
contents of the endosperm of Ricinus under the influence of germination. 
Van Tieghem (3), in a fuller inquiry into the subject, noticed that the 
isolated endosperms of Ricinus under favourable germination conditions 
were capable of respiration, and also of auto-depletion, aleurone and oil 
being consumed under these circumstances. 
He observed that the endosperms of Canna (amylaceous), on the other 
hand, did not under similar conditions exhibit either of these phenomena. 
Van Tieghem concluded that endosperms like that of Ricinus , contain- 
ing copious reserves of aleurone and oil, capable of respiration and auto- 
depletion, were endowed with vitality, while those of the type represented 
by Canna , containing as reserve materials chiefly starch and cellulose, and 
neither exhibiting respiration nor auto-depletion, did not possess vitality. 
The former he termed ‘active’ the latter ‘passive’ endosperms, and 
regarded the digestion of the reserve materials of the latter type as being 
due to the agency of the embryo. 
Brown and Morris (4) subjected to an extended study the barley 
endosperm, and from the results of certain of their experiments advanced 
the view that the amylaceous endosperm of the Gramineae represented 
a c dead storehouse of reserve material ’. This conclusion does not apply 
to the endosperm as a whole, but only to the amyliferous cells, the 
possibility of the aleurone layer cells possessing vitality being left open. 
There is thus a certain amount of agreement in this view with that 
suggested by Van Tieghem. 
Griiss (5) germinated isolated maize endosperms under sterile con- 
ditions, and studied the distribution of diastase in them by means of the 
not very reliable guiac-hydrogen-peroxide test. 
Hansteen’s (6) conclusions are opposed to those of Van Tieghem, that 
self-digestion is confined to oily seeds, and that the endosperms of the 
grasses play an entirely passive part. One of the chief grounds on which 
he bases his objection is that Van Tieghem did not make sufficient 
