414 J. W. Dawson— Paleozoic Land Snails. 
separated by spaces three times as wide. The body whorl 
about 4 millimeters in diameter, with about thirteen vertical 
ridges visible on one side. Length of a specimen probably not 
quite perfect, about 8 millimeters. The shell, which has dis- 
appeared, must have been very thin, and the surface remaining 
is smooth and shining. In general form, so far as can be ascer- 
tained from a very imperfect specimen, this shell must have 
closely resembled the modern Pup of the genus Strophia of 
ers. 
he only specimen known is from. the Erian (Devonian) 
plant-beds of St. John, New Brunswick, which, besides afford- 
ing great numbers of remains of land plants, have produced the 
only Erian insects as yet known. It was sent to me by Mr. G. 
F. Matthew, of St. John, along with specimens of fossil plants, 
several years ago, but I hesitated to describe it, waiting in hope 
of additional specimens. As these have not occurred, and 
I have now carefully examined the whole of the material from 
these beds to which I have been able to obtain access, I venture 
to name it as probably the oldest known land shell, the beds in 
which it is found being either middle or upper Erian. 
If a land snail, it is larger in size and probably of higher type 
than any of those known from the Coal-formation. This odd 
not be wonderful, when we consider the greater variety of sur- 
face and the high character of the vegetation, which, as I have 
elsewhere endeavored to show, distinguished the later Erian 
age in Northeastern America. 
Concluding Remarks. 
It may be proper to mention here the alleged Pulmonifera of 
the genus Paleorbis described by some German naturalists. 
These I believe to be worm-tubes of the genus Sprrorbis, and in 
fact to be nothing else than the common S. carbonarius or S. 
pusillus of the Coal-formation. The history of this error may 
be stated thus. The eminent paleobotanists Germar, Goeppert 
and Geinitz have referred the Spirorbis, so common in the Coal- 
measures to the fungi, under the name Gyromyces, and in this 
they have been followed by other naturalists, though as long 
ago as 1868 I had shown that this little organism is not only 
a calcareous shell, attached by one side to vegetable matters 
and shells of mollusks, but that it has the microscopic structure 
characteristic of modern shells of this type.* More recently 
Van Beneden, Cenius and Goldenberg, perceiving that the 
fossil is really a calcareous shell, but apparently unaware of the 
observations made in this country by myself and Mr. ue- 
reux, have held the Spirorbis to be a pulmonate mollusk allied 
to Planorbis, and have supposed that its presence on fossi 
* Acadian Geology, 2d edition, p. 205. 
