1094 The American Naturalist. [December, 
ZOOLOGY. 
The Molluscs of the Water Mains of Paris.—M. Locard has 
made a study of the malacological fauna of the water mains of Paris as 
represented in the material now in the possession of the Geneva Mu- 
seum. The author finds that the collection embraces 44 species referable 
to 13 genera. Among them are four new species, Dreissensia paradoza, 
D. curta, D. tumida and Amnicola lutetiana. Neither Unios or Ano- 
dontas arefound. The author attributes their absence to the absence of 
fish to which the larvee of these species are in the habit of attaching 
themselves. 
M. Loeard notices four modifications of the molluscs in the water 
mains of Paris from the original types whose habitat is in the waters 
supplying these mains. (1) Diminution of size, due |to absence of 
light. (2) Decrease of coloration owing to the same cause. (3) Modi- 
fications of form, generally a lengthening of the shell, due to the 
mechanical action of a steady, rapid current. (4) Appearance of the 
shells. They are polished, brilliant, uniform, developing with regular- 
ity in a constant medium. (Revue Scientifique, Oct., 1893). 
The Orthopterous Insects of the Galapagos Islands.—The 
various collections of orthopterous insects, the result of nine different 
explorations of the Galapagos Islands, have been examined by Mr. 
Samuel Scudder, and form the subject of a paper published in the Bull. 
Harv. Mus. Comp. Zool., Vol. XXV. The author notes the poverty 
of this Orthopteran fauna. In all there are but 25 species, of which 5 
are cock-roaches, which can in no sense be considered endemic. The 
‘remaining 15 include 7 new species, and are all South and Central. 
American in their affinities. A large proportion of the forms are in- 
capable of flight, which can be accounted for only on the supposition 
that the Galapagos are of recent origin, and that the present Orthop- 
teran fauna is derived from the chance advent of pregnant females 
from the nearest shore, or the shores which currents of the ocean prac- 
tically make the nearest. The insect incapable of flight would stand 
the best chance of reaching the island, since it would have less inclina- 
tion to leave its floating refuge, and thus the exceptional proportion of : 
subapterous forms is explained. 
An Axillary Pocket in Certain Chameleons.—In examining 
a collection of Reptiles sent from Madagascar to the Natural History 
