Og: a= 
Of the 19 species listed, 11 are hemicryptophytes, 7 cha- 
maephytes and 1 therophyte. The percentages are given in 
table 4. 
Leaving out of consideration the one therophyte, (Sisym- 
brium brassiforme) which was found only a single time, and 
is not characteristic for these localities, this last spectrum is 
remarkable for the number of chamaephytes it contains, even 
more than in the horizontal flats of “the Pamirs”. 
From the above we see, first that exposure influences 
the number of the species. This is greatest on slopes with a 
northern exposure, (65), smaller on horizontal flats, (49) and 
smallest on slopes with a southern exposure (19). That is to 
say, that under increasing insolation and resulting drought, 
fewer and fewer species can exist. We may expect, then, to 
find xerophytic adaptation least developed on the slopes with 
northern exposure, and best developed on those with southern 
exposure, 
Next, in regard to the growth-forms, I regret that I have 
not been able on the spot to make a formation-statistical 
examination with a computation of the valence of the species. 
(compare RAUNKIAER.) Instead I must repeat what was stated 
above, namely, that Eurotia ceratoides is by far the most com- 
mon species to be found on slopes with a southern exposure, 
and Stipa orientalis next. In many instances these two are 
the only species to be found. If we consider them equally 
common, we obtain (as valence of growth-form) 50 °/o cham- 
aephytes and 50 °/o hemicryptophytes. As a matter of a fact 
Eurotia should have a higher number than Stipa. 
On slopes with a northern exposure the most common 
species are hemicryptophytes: Poa, Kobresia, Astragalus alata- 
vicus, Oryzopsis, Isopyrum etc. Arenaria Meyeri is however a 
chamaephyte. 
Table 4 shows that when all species are considered 
equally common the number of chamaephytes increases with 
the amount of insolation, but according to what I have just 
stated, if the species, and thereby the growth-forms, had 
frequency-valences, tbe figures would show still greater dif- 
ferences. : : 
In any case, according to the above, we may consider it 
