64 Richard H. Boerker 
the xerophilous species the highest per cents. are in the loam and 
sand, among the xero-mesophilous species the highest per cents. 
are in the sand while in the mesophilous species the highest per 
cents. are in the sand and loam. Out of 34 species, 18.5 ger- 
minated highest in the sand, thus showing the value of this class 
of soil for seed germination. 
TABLE XV 
SUMMARY OF THE Final Germination Per Cent. By NUMBER OF SPECIES. 
Light 
Number of Species 
Greatest Germination Total 
Per Cent in z : Xeromeso- f 
Xerophilous philous Mesophilous 
@Openvlightt: -seceesa 2.00 3.00 T.00 6.00 
Medium shade......... 3.00 7.00 2.50 I2.50 
Denseishadeseeecmccne: 9.00 3.00 4.50 16.50 
MO tal psec eee 14.00 I3.00 8.00 35.00 
Soil Moisture 
IDS Ay ion erie siya cree 0.00 ates BR 0.00 
Medium wet soil....... 3.00 I.00 nays 4.00 
Wietssoilians.cricus cieeer II.00 12.00 Breese 23.00 
MO talc Boia a etecetake 14.00 13.00 aoe 27.00 
Soil Texture 
1 E70 ye coluen eres of eecanien eects 6.00 I.00 2.50 9.50 
Sat Gr ereevsa dhe ioxs ai share geen 5.00 8.00 5.50 18.50 
Gravieliccn 25 scutes 3.00 2.00 I.00 6.00 
Ota sac ce ansteaentieroe I4.00 II.00 9.00 34.00 
THE EFFECT OF HABITAT FACTORS UPON STEM AND ROOT 
DEVELOPMENT 
Following the experiments upon germination, some of the 
species were grown for several months for the purpose of ob- 
taining root and stem measurements. Since damping-off re- 
duced materially the number of seedlings as time went on, the 
number of plants upon which final measurements could be taken 
was naturally reduced. Hence the results are not based upon as 
many measurements as was originally intended. 
