SHERMAN—DORMANT SEEDS 9 
1921] 
TABLE II 
CATALASE ACTIVITY IN Crataegus DURING DORMANCY 
Numeer oF Weicut oF OXYGEN (CC.) LIBERATED AFTER 
DAYS MATERIAL 
ag Hah (cm.) I minute 3 minutes 5 minutes Io minutes 
a Aa rae 0.0410 es! 3.7 17.9 22.9 
Oia 0.0690 4-4 10.6 14.3 18.8 
Bees eb a oe 0.0778 og 15:0 20.0 26.2 
Oe ec cere 0.0773 II.9 ayo2 36.0 45.5 
7 Ree ne be 0.0791 E763 42.9 57.0 65.8 
So} ena ap ie ©.1007 25.6 57.2 65.2" 67.0 
*There are two — explanations for small in talase activity from the 42nd to 
the 128th day: (1) the amount of oxygen liberated may yon Dek limited by the use of wae: 5 cc. of 
dioxogen; (2) adetermination should have ened coo at 2 Asad when after-ripening was complete. 
ndary dormancy 
After that time the seed may go into a seco! 
TABLE III 
CATALASE ACTIVITY IN Amaranthus retroflexus (0.13 GM. IMBIBED SEEDS USED) 
UMBER OF OXYGEN (CC.) LIBERATED AFTER 
DAYS AFTER 
eke cima I minute 3 minutes 5 minutes ro minutes 
Brinn tae 3.0 6.2 7-9 9.2 
ROD aay ea a 2.3 5.0 6.2 7.3 
Oi aes 3-4 6.2 7-7 9.9 
EA eRe ee een 3:8 73 8.9 10.4 
RESPIRATION 
Table IV embodies the comparative respiratory behavior of 
all ten seeds. While all but Rumex have a respiratory quotient 
less than unity, indicating an oxygen intake in excess of the carbon 
dioxide elimination, the value of the carbon dioxide-oxygen ratio 
varies within wide limits. For the Rosaceae the “respiratory 
intensity,” as measured by the milligrams of carbon dioxide 
eliminated per hour per gram of imbibed seeds, averages about 
0.08, while in the other seeds it is higher, being about o.11 in 
Amaranthus, and 0.15+ in Rumex and Chenopodium. This ditfer- 
ence may be due to the character of the storage substance, chiefly 
starch (44), present in the last three seeds, but it is undoubtedly 
also attributable in part to a difference in degree of dormancy. 
