— 160 — 
On the other hand the spectrum of Transcaspia agrees 
in the main with the spectra for Samos, the Libyan desert, 
Cyrenaica and Death Valley respectively. The point of maximum 
intensity for all these spectra lies in the Therophytes. In the 
hotter of these areas, the Libyan desert and Death Valley, 
the Chamaephytes and the Fanerophytes are also prominent. 
As regards its biological spectrum, Transcaspia thus 
presents the same type as the countries of the Mediter- 
ranean, at least the eastern parts. We are further led to the 
conclusion that parts at least of the western countries of the 
Medit rranean should also be included here because 35 per 
ct. Therophytes are found on the Iberian steppes (WILLKOMM 
1894 p. 280). 
* these Therophyte-spectra ‘* ontingent upon the 
same climate: winter-rains and 4%, ury hot summer. This 
forms a link in what is termed by RAUNKIÆR a C-climate 
series, i. e. a series starting at the Equator with a tropical 
moist climate, its continuation northwards being determined 
in this way, that although the heat decreases so does the 
precipitation at least as regards the summer. Thus we get 
a dry climate characterised by a “Therophyte spectrum”. 
Still farther north the precipitation again increases, and we 
have here a temperate Hemicryptophyte-climate which in 
arctic countries is succeeded by a Chamaephyte-climate. Such 
C-climate series are especially met with in the western parts 
of large continents. Death Valley shows the unfavourable dry 
climate in the series which runs through western America. 
Transcaspia and the countries of the Mediterranean represent 
the corresponding link in the series through the western parts 
of the continents of the Old World. 
The B-Climate series passing through the eastern parts 
of the continents, and which has a favourable precipitation 
throughout does not come within the scope of this memoir. 
If on the other hand we compare the spectrum of 
Transcaspia with those of Yekaterinoslaw and Pamir, we 
arrive at the result that whether we proceed from Transcas- 
pia northwards to the south Russian steppe, or upwards 
into the mountains, the Therophytes decrease, while the 
Hemicryptophytes increase in number. This is in accordance 
