of the Herbarium of Acharius. 3138 
his herbarium at Rostock hundreds of specimens which he was 
unable to refer to any one of his types. 
Some faulty determinations here also disfigure the Acharian 
herbarium : thus we find in it an entire series of C. deformis, 
from Sweden, under the name of C. jimbriata; and C. macilenta, 
from Switzerland, under that of C. fimbriata fibula; the typical 
C. pyxidata and its variety chlorophea are intermingled with 
fimbriata; and some specimens of C. cenotea bear at the same 
time, though with a mark of doubt, the two names of cenotea 
and of fimbriata. 
13. Cladonia gonorega, (Ach.) Syn. p. 258 et hb. ejusd. 
When I examined, in the Acharian herbarium, and still more 
in that of Flérke, the long series of specimens intended to justify 
the varieties created by these authors, I could not refrain from 
asking what advantage science could possibly derive from such 
numerous and subtle distinctions. They rather serve to em- 
barrass than facilitate lichenology, and are by no means suffi- 
cient to denote all the forms of a species so variable as C. dege- 
nerans. Moreover the herbarium at Helsingfors contains, under 
the name of forme variantes, more than forty specimens of this 
species which Acharius was unable to compress into his classi- 
fication. 
In my opinion, the forms aplotea, euphorea, anomea, pleolepis, 
lepidota, cladomorpha, polyphea, scabrosa, virgata, and graciles- 
cens do not deserve to be distinguished as particular forms ; and 
this is also the opinion of Acharius himself (Syn. p. 258), “ vix 
sub nominibus singularibus denotari merentur.” 
The form trachyna is more remarkable, and especially more 
easily recognizable ; it may therefore be retained by uniting 
with it the forms lepidota, pleolepis, and virgata. 
As to the variety nivea, Ach. (Syn. p. 260), it belongs to C. 
pungens, Flk.; and Acharius, on revising his herbarium, after 
his Synopsis was printed, unites it with that species. 
Notwithstanding these diminutions, C. degenerans will still 
reckon a certain number of varieties; for the forms hypophylla, 
pleolepidea, and basima, recently described by Dr. W. Nylander 
(Lich. Scand. p. 54), appear to me sufficiently remarkable to be 
elevated to the rank of varieties. I have this summer found all 
these forms in great abundance on the borders of the Baltic Sea, 
both in Sweden and Russia. 
The Acharian herbarium here also contains many erroneous 
determinations: thus, under the name of gonorega appear a 
specimen of C. turgida, from Sweden, two of C. pywxidata, ina 
proliferous state, from Switzerland, and a tuft of C. furcata 
crispatella, F\k., from Sweden. Two forms of C. glauca, Fik., 
Ann. & Mag. N. Hist. Ser. 3. Vol. xvii. 22 
