94 ANDREWS & BEALS: GROWTH OF ZEA MAys 
1. The seed coat was removed from the large end of the unsoaked Zea Mays 
sa which resulted as follows after 60 hours growth. The average growth of 25 
12mm. The lengths of the seedlings in millimeters was as follows, 63, 
57, 27, 27, 19, 18, 15, 13, II, 9 7, 4+ 3, 3, 2, 2, 1; while 8 showed no grow wth. he 
average growth of 25 seedlings with coats intact was 4.6 mm. The length of these 
seedlings was as follows, also in millimeters: 36, 26, 20, 10, 9, 8, 2, 3, I, I, 1; while 
14 showed no growth. 
2. The coats were removed from the embryo side of the unsoaked grain and the 
grain left in the sawdust for 43 hours. The average length of growth of 25 grains 
was 1.4mm. The lengths of the seedlings was as follows in millimeters: 17, 12, 4 
3, 2, I, I, 1; while 17 showed no growth. The average of 25 grains with intact coats 
was 0.04 mm., since the only grain germinating made a growth of 1 mm 
. rhe s were removed from one side of Zea Mays grains and after 48 hours 
oe bea the following growth. The average growth of 22 grains was 1.9 mm.; 
the lengths attained by the seedlings were as follows in millimeters: 12, 8, 7, 4, 2, 
2, 2, 2,1, 1,1, 1; while 10 had no growth. The grains from which the coats had not 
been partially removed did not make growth enough to break through the coats. 
These experiments show the decided advantage a grain of Zea Mays has when parts 
of the coats are removed and show that the absorption of water by the endosperm 
takes place under such circumstances much more rapidly. In this connection it is 
interesting to consult the paper of A. J. Ewart and Jean White on ‘‘ The Longevity 
of Seeds 
II. EFFECT OF AERATION ON THE GROWTH OF ZEA MaAystT 
This experiment was conducted for the purpose of ascertaining 
the effect of aération on the growth of Zea Mays. In water cul- 
tures, as commonly conducted, the factor of aération is one that 
is generally neglected. The plants were grown in most cases as 
water cultures according to the formula as given by J. Sachs. The 
cylinders used had a capacity of 1.5 liters and the solution was 
changed at frequent intervals. The aération apparatus used in one 
set of experiments was that of Kekulé, as described by Ostwald.t 
The other piece of apparatus used for aération was the stern tes 
filter pump. 
Sachs was the first to experiment with an aération apparatus 
on water cultures. This apparatus he illustrates on page 268 
and describes on page 269 of his Vorlesungen iiber Pflanzen- 
physiologie. The apparatus of Sachs is simple but requires more 
or less attention, while either of the pieces of the apparatus used 
for aération of the cultures mentioned in this paper can be regu- 
lated and left for long periods of time to run safely and regularly 
* Proc. Roy. Soc. Victoria 21: 1-203. 1908. 
+See Beals, C. C. The effect of aeration on the roots of Zea sant: Proc. 
Indiana Acad. Sci. 1917: 177-180. f. 1-3. 1918. 
t Manual of physico-chemical measurements 189. 1894. 

