66 
This shell, which sometimes reaches to full three inches in length, 
has six or seven turns in the spire ; the last, or body-whirl, is large 
and globose : the left lip sometimes rising in a strong ridge ; and is, 
as well as the right lip, very smooth on its inner side : the columella 
is disposed to be umbilicated, and the aperture is nearly oval, termi- 
nating in an open canal. 
The original shell, with the twirls passing from the left to the right, 
of which the one just spoken of may be considered as a variety, has 
not been yet mentioned as having been found in the Essex cliff. Dale, 
indeed, queries whether Buccinum rostratum, out of Harwich cliff, 
thus mentioned by Woodward, Catalogue, Part n. p. 37, e. 115, may 
not be referable to this shell : but this can hardly be supposed, from 
so general a designation ; since, having so strongly particularized the 
reverse shell, it is not likely that he would have omitted to point out 
this as being the same shell, turning in the ordinary direction. 
In the many visits which my late respected friend, Dr. Menish, paid 
to this cliff, he discovered two specimens of this shell, with the whirls 
in the ordinary direction. My repeated researches having been always 
unsuccessful, I purchased these shells from Dr. Menish’s collection. 
One of these seems to differ from the heterostrophe in not having its 
whirls so obliquely disposed, in the spire not being so long, in the 
aperture being every way larger, and in the left lip rising higher, and 
being larger and more detached. The other is a very old shell, and 
measures full five inches in length, and three in width. 
A shell, which has been supposed to resemble this last-mentioned 
fossil, has been found on the coast of New Holland ; but the columella, 
in this shell, is so nearly naked, as, I think, renders it specifically dif- 
ferent. A recent shell is, however, found on the Essex coast, turning 
the right way, which very nearly, if not exactly, agrees, in its specific 
characters, with the heterostrophe. 
Lamarck describes seventeen species of this genus as found fossil in 
the neighbourhood of Paris : M. tripterus , M. tricarinatus, M. contabulatus , 
