1911] GOODSPEED—TEM PERATURE COEFFICIENI 221 
duration of life of seeds might yield interesting results if the 
determinations could be made sufficiently accurate. Experiments 
were accordingly begun September 1, rgro, and continued for 
some three months. It seemed to me that the use of barley in 
such an experiment would possibly yield results of the most scien- 
tific interest, since, from the observations of KircHHoFF® to the 
comprehensive researches of BRowN and Morris’ and others, 
this member of the Gramineae has been the subject of much inves- 
tigation. 
The material was obtained from the American Hop and Barley 
Company, grown at their ranches in Butte County, California, 
and harvested during August 1910. The grain was given no 
specific name by the company, but is known in the trade as malt 
or brewing barley. Through the courtesy of the company, a 
quantity of their best grain used for exhibition purposes was at 
my disposal. It was characterized by them as being a trifle under 
the maximum weight, but uniform throughout and of the best color. 
Previous to every temperature determination, the inferior 
palea of each barley grain was carefully removed, and 50 seeds 
were soaked in tap water for one hour. The material thus pre- 
pared was used within ten minutes after being removed from the 
water. It was judged that the removal of the outer seed coat 
would obviate the source of error that might otherwise be intro- 
duced through the different degrees of resistance to penetration 
offered by the protective coverings. By soaking previous to the 
experiments it was hoped that sufficient water would enter the 
tissues of the grain to affect a more rapid adjustment of the tem- 
peratures within and without the seed when placed in the water 
ath. The use of more than 50 seeds for each determination was 
Considered to be unnecessary, inasmuch as control experiments 
including over 2000 seeds gave only 0.4 per cent as the percentage 
that would not germinate under normal conditions. This source 
of error may be considered negligible. 
Two methods were employed for maintaining a constant 
temperature. In the first a double water bath heated by a Bunsen 
* Kincuworr, ScHWEIG’s Journal 14:389. 1815. 
” BRowN and Morris, Jour. Chem. Soc. §7:458- 
