— 163 — 
species somewhat smaller than the number of summer-annuals. 
In the case of several of the other countries given in the 
table, there was the same difficulty in obtaining reliable 
comparative data as to the life-period of the plants, therefore 
I am obliged to limit the table to a comparative statement of 
the flowering season for all the countries. This table will 
to some extent illustrate the proportion between ephemerals 
and summer-annual plants. 
The four upper lines are given for comparative purposes. 
The figures for Denmark are calculated from RAUNKL&R’s 
Excursion-Flora, for Yekaterinoslaw according to BEKETOFF, 
for Samos according to STEFANI, FORSYTH MAJOR & BARBEY, and 
Haracsy, and the figures for Spain according to WILLKOMM 
(1852)'). No figures are given for the Libyan desert, as the 
flowering season is not recorded in ASCHERSON and SCHWEIN- 
FURTH’S flora, also because many of the annual plants are 
facultative biennials or perennials, and some flower both in 
spring and winter. The following species of annual summer- 
plants comparable to those occurring in the Transcaspian 
desert — i. e. not facultative perennials — are given by 
VOLKENS for the Libyan desert: Moricandia clavata, Diplotaxis 
Harra, Monsonia nivea, Mesembryanthemum crystallinum, M. 
nodiflorum, M. Forskalei, Aizoon canariense. Although this 
list be not complete, it indicates that there are very few 
summer-annual plants in the Libyan desert, so that probably 
this locality should have been placed at the foot of the 
table, being the one with the greatest number of ephemeral 
plants. 
The desert of western North America might be placed 
in the table beside Transcaspia. According to THORNBER 
there are in the desert of Tucson about 20 per ct. ”long- 
lived annuals“ and 80 per ct. short-lived ones. By counting 
up SPALDING’s list (1909) of the plants of the Tucson country 
I obtained respectively 21 and 79 per ct. of these two cate- 
gories. The proportion thus agrees approximately with that 
found in Transcaspia. 
1) See also WILLKOMM 1896 p. 150. This work cannot be employed 
for statistics, as all the species of the formations are not recorded, 
117 
