1918] © LONG—DESICCATION AND RESPIRATION 355 
possible and katabolism would go on without extensive repair. 
No. 23 of the series referred to was chosen for this purpose, because 
in treatment, appearance, and amount of water loss it was com- 
parable to no. 22, a plant desiccated in the open, the analysis of 
which has been recorded. It is entirely probable that in the 
composition of its tissues no. 23 when put into darkness was similar 
to no. 22 at the time of its analysis, that is, was characterized by a 
high content of the sap in soluble non-reducing sugars. The results 
of the analysis of no. 23 after 22.5 months in darkness are given 
in table I, in which the corresponding analyses for nos. 7, 22, and 34 
are quoted from the article already referred to for comparison. 
Although it had lost 57 per cent of its original weight in the entire 
course of its desiccation (12 per cent after it was put in darkness), 
when removed from the dark chamber it was still of healthy 
appearance, green at the apex, and only slightly yellowed along the 
apices of the spiny ridges, and MacDovceat ventures the statement 
that it would have put out new roots had it been returned to the 
soil in such condition at the proper season. 
TABLE I 
RESULTS OF ANALYSES OF TISSUES OF Echinocacius 
| 
No. 23; po und 
ed in full s 
ht 8 ths, No. 7; desiccated No. 22; desiccated 
oy 4 3 months in diffuse light - in full onaligtt 5 | No re normal, er 
Analyses made Aptian 22) years, r month; ionths, 6 days; | **° alice 
onths, 17| total water loss pga water loss 40 | 
days; total} 29 per cent 
water loss 
nt 8 
Tissue sample. ...... ab c a b c a b oy a | b | ‘c 
H 
or weight per cent of | 
5 ger weig : Be RN 20.2 WY [os 1.6 15.8 “ 3° (13.3 |1t-3 | 5.8 | 4-2 | 3-6 
ap density (water= 
cf EO Res t.o18 1.035 | r.0f0| r.0r8) 1.013) 1.016) 1.027) I. pp r.0r3) tf. — gee 
Sap ac aridity, N/ 20... 0.600 | 0.400 | 0.144) 0.104) 0.148 0.244) 0 208) 0. 6 0.172 0.156, Oo. 
Total hydro rage | 
ca drate | Ks 
cent of total solids. ar. ¢ 28.2 22.3 |24.2 |1%. [44.3 [44.2 [43-4 (32-3 85-7 
Total reducing Ts: i | 
per cent t of £ tote sa’ 
WENGE esas se ts 08 Trace | 0.09 | 0.06 | 0.04 | 0.15 | 0.13 | 0.10 | 0.53 0.42 | 0.10 
Total ni LIC | 
on-reducing 
Sugars; per cent of, 
total sap weight .. | Trace Trace St ere 0.06 | 1.28 | 1.48 2,67 | 0.44 | 9-83 0.05 
In table I, a, 6, and c represent certain arbitrarily defined 
tracts in the cortex of the plant, a and 6 (joined in the case of no. 23) 
