May 3i, 1924 Cell Sap Density and Environmental Conditions 
873 
Table IX .—Freezing point depressions and osmotic pressures of the sap of herba¬ 
ceous plants, including grasses and a moss on Big Cottonwood Canyon water¬ 
shed, classified by species, type, situation, altitude, and date of collection —Con. 
[Figures in italics represent averages of two or more determinations] 
Species and type 
Situation 
. 
Alti¬ 
tude 
Date of 
collection 
Depres¬ 
sion of 
freezing 
point 
Os¬ 
motic 
pres¬ 
sure 
Elephantella groenlandica (Retz.) Rydb. 
(=Pedicularis groenlandica Retz.) 
Spruce-fir__ 
Northern aspect. 
Feet 
8,800 
1920 
July 25 
Degrees 
C. 
1.15 
Atmos¬ 
pheres 
13.8 
Equisetum laevigatum A. Br. 
Chaparral_____ 
Southern aspect.. 
6,400 
July 21 
1. 25 
15.0 
Erigeron speciosus (Lindl.) DC. 
Spruce-fir__ 
Northern aspect-... 
8,950 
Sept. 9 
0.99 
11.9 
Eriogonum heracleoides Nutt. 
S prime-fir _ _ 
E astern aspect.. 
9,000 
...do_ 
1.04 
12.5 
Eriogonum neglectum Greene 
Chaparral_ _ __ 
Southern aspect..•_ 
7,500 
7,500 
July 19 
Sept. 6 
1.80 
21.6 
Do . 
...do_ 
l.tf 
17.6 
Festuca confinis Yasey 
C haparral_ _. _ -____ 
Southern aspect. 
7,500 
Sept. 12 
1.58 
19.0 
Fragaria platypetala Rydb. 
Aspen-fir_ 
Northern aspect. 
7,450 
7,450 
July 22 
Sept. 13 
1.11 
13.4 
Do...- 
Northern a~spect, under 
aspen. 
0.49 
5.9 
Frasera speciosa Dougl. 
Aspen-fir_ 
Northern aspect. 
7,450 
July 22 
1.12 
13.5 
Geranium viscosissimum F. & M. 
Aspen-fir_____ 
Lower southern aspect_ 
Northern aspect_ 
7,450 
7,500 
7,500 
July 26 
1.16 
14.0 
12. 5 
Do _ __ . . 
July 13 
Sept. 13 
1.04 
Do_ 
.do.1. 
0.72 
8.7 
Gilia aggregata (Pursh) Spreng. 
Spruce-fir_ 
Northern aspect, open..... 
8,850 
Sept. 12 
1.26 
15.2 
Heracleum lanatum Michx. 
Aspen-fir_ 
Northern aspect. 
7,450 
July 19 
1.00 
12.0 
Humulus lupulus neomexicanus Nels. & 
Cockerell 
Aspen-fir__ 
Northern aspect. 
7,450 
July 27 
0.85 
10.2 
Ivesia gordonii (Hook) T. & G. ( =Horkelia 
gordonii Hook.) 
Spruce-fir_ 
Eastern aspect, open. 
9,000 
Sept. 9 
0.89 
10.7 
Lappula floribunda (Lehm.) Greene 
Aspen-fir_ 
Northern aspect_ 
7,450 
10,000 
July 27 
0.70 
8.4 
Spruce-fir _ ___ ____ 
Ridge-top_ 
July 15 
0.81 
9.8 
Lathyrus coriaceus White 
Spruce-fir_ 
Northern aspect, open. 
10,000 
July 15 
0.93 
11.2 
Linum lewisii Pursh. 
Spruce-fir__ 
Eastern aspect, open. 
9,000 
Sept. 9 
1.40 
16.8 
Lithospermum ruderale Dougl. (=Z. 
pilosum Nutt.) 
Aspen-fir. 
Lower southern aspect..-- 
7,450 
Sept. 6 
1.18 
14.2 
