THE NAUTILUS. 
131 
Navarchus. —In working upon the Tectibranchs for Vol. XVI 
of the Manual of Conchology, I find that the name Navarchus, ap¬ 
plied to a group of Doridiidce, is preoccupied. I propose, therefore, 
to substitute Navanax, the type being N. inermis Cooper. 
Pleurotomaria Beyrichi.— A specimen of this rare species 
has lately been added to the National Museum Collection, which 
now possesses three of the four recent forms of the genus. 
Note on Potamanax. —The name given tothisgroup of tropical 
American Melanians has been used again for a genus of Lepidoptera 
(Watson, Hesperidce, P. Z. S., 1893, p. 55). As the signature of the 
Proc. Acad. Nat. Sci. Phila. containing the description of the mol- 
lusk genus was actually distributed on Jan. 24, 1893, and the paper 
containing the Lepidopterous genus was printed under the proceed¬ 
ings for Jan. 17, 1893, the latter has apparent priority. However, 
the proceedings of that meeting could hardly have been actually 
printed until some weeks after the meeting, so that it is extremely 
probable that the name of the Lepidopter is later in date of actual 
publication, and must, therefore, be changed. 
We are indebted to Dr. W. D. Hartman of West Chester, Pa. 
for the illustrations of Unio ochraceus and U. cariousus in this 
number. They are from his Conchologia Cestrica, an excellent 
work describing and figuring the shells of Chester Co., Pa., and 
incidentally the majority of those of the Middle States. 
Anatomy of Hemktvcla.— Dr. A. Krause (Nachbl. D. M. 
Ges. Jan.-Feb. 1895, pi. 1) has recently dissected several species of 
this Canary Island group of Helices, and finds their anatomy to be 
practically identical with that of Tachea. The rank and position 
assigned the group in Pilsbry’s “Guide to the Study of Helices” is 
therefore fully confirmed. Its relationships are not with the 
Madeira and Azores Helices of the genus Leptaxis, but with the 
forms of true Helix of the European and N. African mainland. 
NEW PUBLICATIONS. 
The Zoological Record for 1893 has appeared, containing the 
records of Mollusca, Brachiopoda and Bryozoa, by Mr. B. B. Wood¬ 
ward. These digests of the literature of zoology are of such great 
utility, when well done, that we cannot refrain from congratulating 
the Zoological Society upon the admirable manner in which the 
present Recorder has performed his difficult task. Mr. Woodward 
should have the hearty cooperation of all the conchologists. His 
