1921} 9) PACK—JUNIPERUS 59 
higher temperatures until germination has started. If these seeds 
are given sufficient time they will germinate, even at o* 1° C. 
/ 14, Subsequent to after-ripening and germination at s-; the 
best, temperature for seedling development is 1  <., 
12. The development of chlorophyll in the juniper seed and 
seedling was found to be independent of light, but conditioned 
by the temperature range. Seedlings grown at temperatures of 
o*1°C. or 30°C. never developed chlorophyll. Anthocyanin 
development in seedlings seems to depend upon relative tempera- 
ture and carbohydrate supply. 
~~~13. A more complete chemical analysis of these seeds at differ- 
ent stages of development will be given in a later paper. 
Acknowledgments are due Dr. Witt1am Crocker and Dr. S. H. 
ECKERSON, under whose direction and criticism this work was 
carried on. 
AND M. CoLiEecEe 
CoLLece Sration, TEXAS 
LITERATURE CITED 
1. APPLEMAN, C. O., Relation of oxidases and catalase to respiration in 
plants. Amer. Jour. Bot. 3:223-233- 1916. 
Atwoop, W. M., A physiological study of the germination of Avena fatua. 
Bor. Gaz. §7:386-414. 1914. 
Brurens, W., Uber die Beeinflussung der Keimfahigkeit gewisser Samen 
durch Narkose und Verwundung. Bericht. Grossh. Bad. Landw. Versuch. 
seein fo 60-64. 1906. 
4. BRUYNING ., On the use of hot water for forcing germination of hard 
coated seeds. he Landw. 41:86. 1806. 
5. Crocker, W., Mechanics of stage Amer. Jour. Bot. 3:99-120. 1916. 
6. CROCKER, W., and Harrincron, G. T., Catalase and oxidase content of 
seeds in rolation to their eoanty. age, vitality, and respiration. Jour. 
Agric. Res. 15:137-174. 1918. 
7- CzaPEk, F., Biochemie der Pflanzen. 1:710. Jena. 1913 
V8. Davis, W. E, and Roser, R. C., The effect of external conditions upon 
the after-ripening of the seeds of Crataegus mollis. Bot. Gaz. 54:49-62. 
1912. 
- Dutcuer, R. ApaAms, Vitamine studies. 
1918 
: paces. S. H., A physiological and chemical study of after-ripening. 
Bor. Gaz. 55:286-209. 1913. 
he 
iH 
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