Miscellaneous. 443 
to Dr. Carpenter the number is variable, Prof. Verrill having counted 
from four to six in some specimens. These fenestrae in this species 
are more complicated than in most chitons which I have examined. 
I have never been able to satisfy myself that there is a true oviduct ; 
and it may be that the ova are dehiscent in the perivisceral cavity, 
and may be expelled through the fenestra, as they are through the 
analogous ‘‘ oviducts or segmental organs” of brachiopods. 
The fact that the ovarian openings are not simple apertures was 
noticed by me in dissecting chitons in 1869, but I am not aware that 
attention had been previously called to this fact in print. Their posi- 
tion had been previously known ; but it is not uniform in all chitons. 
In some the fenestree are close to the anus and single on each 
side; and it has been stated that the ovary of one side is sometimes 
abortive. This last I have not yet observed in any species which I 
have dissected.— Bulletin of the Essex Institute, vol. vi., Aug. 1874. 
“Boreal and Arctic Shells.” 
We beg to call the attention of our readers to the following commu- 
nication received from the Secretary to the Smithsonian Institution. 
To the Editors of the Annals and Magazine of Natural History. 
Smithsonian Institution, 
Washington, D. C., March 16, 1875. 
Dear Sirs,—Mr. W. H. Dall has been engaged since 1865, under 
the auspices of the Smithsonian Institution, in prosecuting researches 
in regard to the marine invertebrates of the region lying between 
America and Asia, from latitude 50° to latitude 70° N., including 
the coasts of Russian America, the Aleutian Islands, Behring Sea 
and Strait, and the Arctic Ocean north of the Strait. He is now 
occupied in working up his collections at the Institution, with special 
reference to correlating the species of the Arctic fauna, and their 
relation to those of both the Atlantic and Pacific seas. 
The Smithsonian Institution is desirous of obtaining suitable 
material for his comparisons, especially from the coasts of Greenland, 
Spitzbergen, Norway, and Sweden, the northern coast of Russia, and, 
in general, the boreal seas of Europe. While any and all marine in- 
vertebrates will be acceptable, Mr. Dall at present is especially anxious 
to secure, as soon as possible, all the arctic and boreal species of Tuni- 
cates and of Shells, and especially such as contain the animal, either 
dry (if Gasteropoda) or preferably in alcohol, and for the commoner 
species large series and from as many different localities as possible. 
In return for such contributions the Institution offers a series 
from Mr. Dall’svery extensive collections, which will be supplemented, 
if necessary, by duplicates from the collections of the U.S. Fish Com- 
mission made on the east coast of the United States, and identified 
by Prof. A. E. Verrill and other collaborateurs of the Commission. 
Any valuable specimens which may be lent for examination will 
be carefully preserved, and returned at as early date as possible. 
Specimens may be sent through any of the European agents of 
the Smithsonian Institution. Very respectfully, 
JoserH Henry, Secretary §, I. 
