702 
Miller.—A Physiological Sludy of the 
The proteid is present in the form of granules or grains, and according 
to Osborne and Campbell ( 30 ) consists principally of the globulin edestin. 
All the cells of the seed, including the rudimentary root and 
hypocotyl, are closely packed with reserve material. 
Stage I. At this stage the hypocotyls and roots of the 
seedlings have reached a length of from 2-5 to 3-5 cm., and 
have the appearance shown in Fig. 2. The reserve material 
at the beginning of germination first disappears from the 
stretching tip. The disintegration and disappearance of 
material then take place in the lower end of the cotyledon. 
At this stage the reserve material has disappeared, for the 
most part, from the hypocotyls and roots, and the proteid 
grains have broken up in the lower third of the cotyledons. 
Fig* 2* Stcip’c 
I of Seedlings. The proteid matter in the upper two-thirds of the cotyledons 
is apparently yet intact. Starch can now be detected in the 
starch sheath of the hypocotyl. The root tip is now active 
as a growing point, and the root is increasing in length in the 
usual way. 
Stage II. The hypocotyls and roots have now reached 
a length of 7*5 to 11-5 cm. The seedlings were just breaking 
the ground and the cotyledons were not yet separated from 
the seed-coats. The cotyledons as yet were only yellowish 
in colour. The time required for the seedlings to reach this 
stage was from 4-| to 5 days. The proteid material at this 
period has disintegrated into small granules in all the cells of 
the cotyledons. It has almost all disappeared from the lower 
part of the cotyledons, and the cells in that region are 
beginning to form vacuoles. The starch sheath is filled with 
starch as in the preceding stage, and starch also makes its ap¬ 
pearance in the parenchyma of the mid veins in the lower part 
of the cotyledons. See Fig. 3. 
Stage III. The time required for the seedling to reach 
this stage was about seven days. As soon as the plants had 
appeared above the surface of the ground the pots and pans 
containing them were transferred to the apparatus free from 
C 0 2 and kept there until they had made the desired growth. 
The seedlings in this stage were kept in the C 0 2 -free apparatus 
one day. At this stage the cotyledons had become a bright 
green and were spread out perpendicular to the hypocotyl. 
Fig. 3. Stage JL, . . , , , . , J \ J 
II of Seedlings. The hypocotyls had now reached a length of 5 to 0-5 cm. 
above the ground. The root had reached the same length, 
while the side roots had attained a length of from 2-5 to 3*5 cm. See 
Fig. 4. The plumule had as yet not developed. The cells of the starch 
