1921] PACK—JUNIPERUS 41 
activity. At the forty-fifth day the remaining seeds were exposed 
to atmospheric air. Table VIII gives the catalase activity for the 
same lot of seeds at the end of 95 days, 50 days after replacing the 
oxygen by air. The point of interest here is the fall in catalase 
TABLE VII 
EFFECT OF OXYGEN ON CATALASE ACTIVITY OF SEEDS STORED 
45 DAYS AT 25° 
PERCENTAGE OF OXYGEN IN CC. LIBERATED DURING 
OXYGEN Lor 
I min. 5 min. Io min. 
SO ee y os 4.4 4.8 
ee nee 2 3-4 5-3 5.6 
ee ne Petar he aur 3 3.7 6.2 6.6 
Fete eae wee og 4 4.8 75 8.8 
Air (ehtek) fishy 3.8 6.2 6.9 
TABLE VIII 
REDUCED CATALASE ACTIVITY IN OXYGEN TREATED SEEDS WITH 
IECREASE IN PERCENTAGE OF OXYGEN 
OXYGEN IN CC. LIBERATED DURING 
Lor 
1 min. | 5 min. | to min. 
Me Gore Pa ue eee 2.5 * | 5.0 6.0 
Fees ya a 2.9 | 5.) 6.1 
3 pa Ee iy is MM emia 2.7 5.0 5.8 
bere ee uy eM EG yet ul ey 2.8 5.0 5.6 
Ais O 2.8 5.5 6.0 
activity, at the ninety-fifth day, for the seeds that were exposed 
to 100 per cent O, during the first 45 days. None of these seeds 
germinated. 
EMPERATURE.—No other condition affected the development 
f the juniper seeds to the extent that temperature did. Both 
alternating and constant temperatures ranging from r15~-30° C. 
were found to reduce the catalase activity and inhibit germination. 
Seeds exposed to winter weather (in soil and on moist filter paper) 
gave about 1 per cent germination. Those subjected to a tem- 
perature of ro~-12° C. in running water showed a steady increase 
of catalase activity up to the time of germination. Between the 
