1883. } Zoblogy 203 
If the cuttings hold fast after three or four weeks, the propaga- 
tion is secure. A characteristic feature of the cuttings is their ten- 
dency to assume a round form. To facilitate this on every side is 
the chief aim of Buccich’s system of supporting on sticks. As to 
the rate of growth of the cuttings within a certain period no rule 
can be given, on account of the varying conditions. 
Buccich remarked that the cuttings in the first year were two 
or three times as large as they were originally ; he further re- 
marked that the cuttings grew better in the first and fourth years 
than in the second and third, a point evidently regarded as doubt- 
ful by Dr. Marenzeller; and it would seem that though some spe- 
cimens may have attained a considerable size in the fifth year of 
transplantation, still a term of seven years is necessary to produce 
a marketable and profitable article. 
Dr. Marenzeller also mentions the fact that besides being beau- 
tifully formed and rounded, the cuttings retain these qualities, and 
perfect health, with increasing size. 
In conclusion, Buccich proposes the question whether the un- 
dertaking can be made profitable, and answers it in the affirma- 
tiv 
e. 
Dr. Marenzeller concludes that the propagation of sponge by 
cuttings is not to be recommended to people without capital, but 
is more suited to the attention of a capitalist, or an association of 
capitalists, and to be conducted on a large scale.— Fournal Royal 
Microscopical Society. 
THE CIRCUMPOLAR DISTRIBUTION OF CERTAIN FRFSH-WATER 
MUSSELS, AND THE IDENTITY OF CERTAIN SpEcrEs.—In a recent 
paper’ suggested by the occurrence of the remains of fresh-wa'‘er 
mussels (Anodons) associated with other fossils in the sedimentary 
Strata of the Carson City prison yard, read by Dr. Stearns before 
the California Academy of Sciences, the author in an elaborate re- 
view of the subject, expresses the opinion that the European 
Ano donta cygnea + Anatina, should be added to the circumboreal 
list with other fresh-water mollusks, including Margaritana mar- 
garttifera, among the lamellibranchs, and Linnea stagnalis, L. 
ustris, and L. auricularia (as represented by L. ampla); Fhysa 
hypnorum and P. fontinalis (by Physa heterostropha), among the 
gasteropods. 
With the exception of A. cygnea, the above species have long 
been regarded by the most conservative authors as circumboreal 
in their geographical range. : 
-The author also considers the Eastern American species, Ano- 
donta imbecilis Say and A. fluviatilis Lea, from New England 
Waters, inclusive also of A. implicata, from the same region as 
identical with A. axatina or some of the numerous varieties of 
es On the History and Distribution of the Fresh-water Mussels and the Identity ot — 
. ic” By Robert E, C. Stearns. Proc. California Acad. Sciences, 
