a. 
60 The Botanical Gazette. [Februay, | 
2. The capillary tube, 2, especially must be free from ait 
bubbles and other impurities. . 
3. All fittings to tube 4 must be air tight. 
4. The tube 4 must be entirely filled with water. 
5. The water used should be boiled to remove air. 
6. The temperature of air and water must be stationary be 
fore observations are made. 
7. Nothing must be placed in 4 that will generate gas 
as culture fluids, etc. ae 
8. The same plant must not be retained in tube @ for mott 
than 12 hours. | 
9. The water in tube 4 must be changed every time tht 
plant is changed. i 
These precautions may assist in preventing faulty expet 
menting on the part of those who may not as yet have ust 
a similar apparatus. 4 
rom a series of experiments I found that the daily peridl 
of maximum transpiration corresponds to the daily period ¢ 
maximum growth (one to four o'clock Pp. M.). This seemst 
be additional evidence that transpiration depends upon & 
similation. a 
I. RELATION OF LIGHT TO EFFECT OF ANASTHETICS | 
The plant used in the following series of experiments We 
Solanum tuberosum. n all cases the plant was covered) 
the bell jar and dry air forced through by means of a pall? 
foot bellows. The air was dried by means of sulphuric att 
and chloride of calcium. Of course the entire plant was use — 
root and all, care being taken not to mutilate the fine rootles 
more than was unavoidable. No observations were ™ r 
until the temperature of the air and water was nearly cof 
stant. a 
- Solanum tuberosum, small plant, seven leaves, Ht 
small, developing tubers; in diffused light. 
elec 2 
Tem.o Ni * : F 
: Tem, of, NOTmal|Time in seconds required to . * 
Time bee air 9c. |. OF €vaporate 5min of water gh es Prog 
. Anaest, column. . a 
: ° |Normal 2 Ether in gi 
$34 MAT A | Mher 8 Seo eos koe a” vet 
7) 7: 8, 7 6, 8, Tm g 
: ’ 8, 9, 9, 10,9 tn 
30: + 5 ‘ Ethert phi 
3:50 | 21349 | 22%° |Normal Fy 22 At, 22) 12, 12, Tz, 23| << F.2- LF. 
: : a 12, Tr, (2, Ir, ro, 8, 7, 8, 7, 7. 8, 7| 1% 4-7.2 it. in! 
4:20} 21° 204° al 7, 7, 8.7, 7,8, 8,7,7.7,8, 7,8, 7} 7.3 sey ‘mit. 
yo eo wets gist we ate 8, 7c. 7558, 7.8, 8,8, 9, B,C 78 et te 
nll ae ss WMS HEC 12, F202, 99.14 8" vg. 95 3c cs, 12.37 eT 
Normaljs3, 13, 12, 12, 13, etc. tomormal.| 12-7.5 ae 
