e 
1877.] Zoölogy. 241 
fresh twigs. But while in the latter the absorbed gas can be driven off 
tolerably rapidly by oxygen, hydrogen, or nitrogen, this happens in the 
first just as in the case of carbon, only more slowly.” ; 
BOTANICAL NOTES FROM RECENT PERIODICALS. — Flora. Batalin, 
Mechanism of the Movements in Insect-Eating Plants (not yet finished). 
Dr. Celakovsky, On the Morphological Structure of Vincetoxicum and 
Asclepias. A. Poulsen, The Occurrence of Crystals surrounded by 
Cellulose (Rosanoff’s crystals detected in the leaf stalks of many Le- 
guminosz). 
Botanische Zeitung. 1877, No. 1. Dr. DeVries, On the Extension 
of Growing Vegetable Cells by Turgescence. V. Waldheim, A Fun- 
gus on Rumex. Nos. 2 and 3, Beyerinck, On Galls. No. 4, Jack, On 
European Hepatice. Continued in No. 5. Dingler, On Lathrea 
rhodopea. 
ZOOLOGY. 
Tue Common Cras (Carcinus Ma@NAS) AT THE HAWAIIAN ISLANDS. 
—I desire to direct attention to the crustacean genus Carcinus, of which 
there is but a single species, menas. In 1873 the writer obtained a 
specimen from the Hawaiian Islands. This is the first well-authenti- 
cated instance, to his knowledge, where the species is recorded as com- 
ing from Pacific regions. In.the Museum of the Academy of Natural 
Sciences of Philadelphia there is a specimen labeled from Australia, 
with an interrogation mark. It is found along the whole coast of 
Europe, from the Baltic to the Mediterranean; it is equally common 
and as widely distributed along our Atlantic coast. Heller reports hav- 
ing found the species on the eastern coast of South America, and it has 
likewise been obtained from the Red Sea; and now the Pacific Islands 
are added as a habitat. In.the latter region, however, it cannot be very 
common, as it has eluded research up to the time mentioned, notwith- 
standing the fact that these islands have been pretty thoroughly ran- 
sacked for this kind of life. It may, however, be considered as cosmo- 
politan, as having a wider range than any other known species of crab. 
! What is particularly interesting in connection with its wide distribu- 
tion is the identity of the species wherever found. Very slight differ- 
ences can be observed in the specimens coming from these widely sep- 
arated localities. ‘The differences are not sufficient to constitute distinct 
species ; at the most they would only form varieties. Carcinologists 
have agreed, however, to ignore the slight geographical variations and 
to designate them all by the same name. 
The difference consists principally in the extent of the granulations 
on the surface of the carapace, and in the prominence of the front. 
Our Atlantic-coast crab differs from the European in having the surface 
2 granular, and the teeth of the front somewhat more prominent ; 
in the Pacific specimen the granulations are larger, and the front more 
Projecting when compared with the former. It will be observed that 
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