fusion still exists among the species; confusion which 
can only be removed by a critical examination of the 
synonymy of each, and by good figures of all the species 
and their principal varieties. 
We suspect that this observation is particularly ap- 
plicable to the subject of the accompanying plate, of 
which, according to Russian and other Botanists, the 
varieties are very numerous; but under which we are 
rather disposed to believe two at least, if not more, distinct 
species are confounded. 
S. chamedrifolia originated with Ammann, from whom 
Linnaeus adopted it. The description of the former of 
these two writers is so good, that it leaves no doubt upon 
our minds that he intended the species now represented ; 
indeed his account will not apply to any other plant: he 
confines its range to Davuria; and he does not advert to 
any supposed tendency in it to vary. 
Gmelin, however, in his Flora Sibirica, declares it to be 
extremely variable ; but the account he gives of the varieties 
makes it more than probable that he is talking of different 
species. This may possibly have predisposed Pallas to 
adopt the same opinion in his Flora Rossica, in which, of 
all the forms he has figured, the single leaf alone, at the 
bottom of the left side of the plate, seems to us to repre- 
sent exactly the species intended by Ammann. According 
to Pallas, it first appears on the east of the Ural Moun_ 
tains, skirting the banks of the Tura, the Ljala, the Cocva, 
the Sosva, and other Alpine streams; becomes abundant 
about the Jenisei, and fills all the woods and thickets of 
the Transbaicaline districts, and especially of Davuria. 
But we believe this, the Davurian plant, is different from 
the others of which Pallas speaks. 
This confusion having been once introduced, a new 
name was given to the true S. chameedrifolia by Scopoli, 
who, not perceiving its identity with the plant of Ammann, 
published it under the name of S. ulmifolia, — an error 
which has been adopted by all succeeding Botanists. 
e now correct this mistake, cancelling the species called 
ulmifolia, as a mere repetition of S. chamedrifolia. 
The Spiræa flexuosa of Dr. Fischer is in all probability 
the same species as S, chamedrifolia ; at least, when that 
