exe met 
Assiminia Grayana. 429 
fies the conclusions formed trom a careful examination. 
I speak with greater caution on the point in deference to Mr. Lowe’s 
experiments on an animal evidently congeneric: and I do not advert to 
them as in the present Number some observations are made upon them, 
in consequence of a communication which was transmitted to him on the 
subject. 
On seeing the animal [ was immediately struck wiih its resemblance to 
that of Physa or rather Aplera. On mentioning this to Mr. G. B. 
Sowerby, he informed me that he has some fluviatile Limneide from 
South America which tend to confirm my suspicion. On the whole, I 
think that there can be little doubt that it is most nearly allied to 4piexa; 
and, as it appears to me, an object of some interest as connecting the 
Limneide with Carychium, Auricula, &c. ee 
ASSIMINIA GRAYANA. 
Foot broadly obovate, obtuse, composed evidently of two distinct 
lamine, the lower projecting beyond the upper, and separated from it 
by an accurately defined line; above fuscous, beneath olivaceous shaded 
with cinereous. 
Tentacula very short and obtuse, fuscous, eyes at their tips. 
Muzzle porrected, not truly proboscidiform, deeply notched in front, 
fuscous, strongly annulated ; the edge of the lip paler: on each side is 
a groove running backwards from the base of the tentacula. 
Mantle open behind. 
Feces elliptical (as in Cyclostoma). 
Operculum corneous, ovate, spirally striated. 
The most remarkable circumstance in this animal is the position of 
the eyes, at the tip of the tentacula, as in Helix and its allies, and not at 
the base. It would appear asif there were in reality no tentacula and 
only the tubercle common to many Mollusca at the base of the tentacula, 
a little more developed than usual. The shell is so like that of some 
species of Rissoa that it is quite surprising that in Dr. Fleming’s British 
Animals and Mr. Jeffrey’s paper in the Linnean Transactions it should 
be placed in or close to the genus Limnea. Dr. Leach seems to have 
formed his conclusions from an actual inspection of the animal, and con- 
