440 Stoward , — On Enddspermic Respiration in Certain Seeds . 
The influence of diminished pressure on the initial output of C0 2 in 
the case of Zea is quite undemonstrable. 
15. Experiments with Chloroform-steeped Material 
(Endosperms and Pure Endosperms). 
Dry degermed endosperms of Hordeum^ after steeping in saturated 
aqueous chloroform for twenty-four to forty-two hours, are still capable of 
manifesting respiratory exchanges ; and the relative output of C0 2 does not 
greatly differ from that observed in the case of water-steeped material. 
Similarly the endosperm of Ricinus also retains its respiratory capacity, 
although in a diminished degree, while the endosperm of Zea is no longer 
able to function. 
Pure endosperms of Hordeum , after twenty-four hours immersion in this 
reagent, were found to have completely lost this capacity. 
The apparently toxic effect on the pure endosperm of Hordeum , and 
its comparatively feeble effect on the endosperm of this seed, suggested the 
possibility of its entry into the endosperm being retarded in some way. 
To gain information on this point a series of imbibition experiments 
were performed with the endosperms of Hordeum . 
The results are given in the following table : — 
Imbibition Experiments. 
Endosperms of Hordeum . 
Exp. 1 . Seeds degermed in dry resting condition; paleae removed as far as possible, 
and parallel series of endosperms steeped in (a) distilled water, (b) saturated 
aqueous chloroform. 
Series. 
No. of 
endosperms. 
Duration 
of steep. 
Medium. 
% of medium 
imbibed. 
% difference 
in favour of 
water. 
‘A.’ 
40 
24 hours 
Water 
52-34 
40 
24 » 
Aqueous chloroform 
49 ’ 3 2 
3.02 
‘B.’ 
20 
2 4 » 
Water 
46.3 1 
20 
24 „ 
Aqueous chloroform 
42*96 
3*35 
‘C.’ 
20 
48 „ 
Water 
55-71 
20' 
48 „ 
Aqueous chloroform 
52*26 
3-45 
‘D.’ 
40 
48 » 
Water 
64*65 
40 
48 „ 
Aqueous chloroform 
55-82 
8-83 
The endosperms of £ B ’ (steeped in aqueous chloroform) were washed 
with water, drained on blotting-paper, bisected longitudinally, and placed 
in a securely corked tube. This tube and its contents were immersed 
in a water bath, and kept at a temperature of 8o° C. for ten minutes ; on 
removal from the bath, quickly cooling to laboratory temperature, and 
uncorking, no smell of chloroform was perceptible. 
