PROCEEDINGS OF SOCIETIES. 
19 
Triclioptera , Dermaptera , Dictyotoptera , Thysanoptera (not to mention the 
Mallophaga and Thysanura ), which, if inadmissible permanently, have, perhaps, 
served a purpose in exciting to more accurate investigation and comparison of 
the distinctive characters, which has ended in a result the very opposite of that 
contemplated—that is, in their incorporation again in one order. The greatest 
apparent difficulty arising out of this re-union, in connection with the place 
determined for the order by the character of its chief component groups, lies in 
the removal of the Plicipennia to such a distance from the Lepidoptera—a 
position which is represented in the circular arrangement by opposite points of 
the circle. Shall we, then, have to betake ourselves to the notion of an ideal 
recurrent, or a double parallel series, with representative analogies between 
opposite points ? 
After some conversation which followed the reading of this paper, Mr. E. Percival 
Wright read the following communication from Edward Waller, Esq., Correspond¬ 
ing Member, 
ON THE OCCURRENCE IN FINNOE OF SOME RARE FRESH-WATER MOLLUSCA. 
Since my list of the land and fresh-water mollusca found at Finnoe was sent to 
the Association, I have discovered a few other species, which, from their rare occur¬ 
rence in Ireland , may be worth noting. 
Scccinea Oblonga. —(Drap.)—In August last I visited a piece of low ground 
where I had formerly collected Succinea Pfeifferi in great abundance, and of a form 
which Mr. Thompson considered typical. I did not then discover any other species 
of Succinea. On my last visit, Succinea Pfeifferi had become rare; but amongst 
them, in various spots, I found a good many of the Succinea Oblonga, agreeing 
very well with the description and figure in Gray’s Turton. This species was not 
given in Mr. Thompson’s list of Irish shells.—(Ann. and Mag. Nat. Hist., Sept., 
1840.) Forbes and Hanley give localities in the extreme south of Ireland. It 
must still be considered a rare shell in Ireland, and it seems to be very local in 
England. 
Vertigo Substriata. —Under stones in a wood, on high ground, at Finnoe, I 
found a good many of this species. I could not discover it beyond a very limited 
space. 
Helix Aculeata. —I obtained an individual of this species at Prior Park, 
which, although not strictly within the limits by which the small district of Finnoe 
was defined, is not more than a mile from it. The shell was found under a small 
stone, part of a heap beneath beech trees. Several careful examinations of the 
ground in the immediate vicinity did not reward me with another specimen. 
Anodon Cygneus —Procured at Prior Park, from a small deep lake, out of 
which a very small stream, flows to the Shannon. 
There are thus four species added to the list of Finnoe shells. The Succinea 
Oblonga rarely exceed three lines in length. In Gray’s Turton this shell is said to 
be like Limneus Fossarius in shape. This may be true in a front view ; but, look¬ 
ing at the outer lip in profile, any one at all acquainted with the general shape of 
Limneus will see the difference. The folding of the inner lip is a generic distinc¬ 
tion easily observed. It may have been mistaken and passed over by inexperienced 
collectors, but may be readily distinguished by a little attention. On comparing 
some of these shells with specimens of Succinea Angustior, of Adams, sent by Mr. 
Chitty from Jamaica, to the Royal Dublin Society, there did not appear to me any 
difference on which to found a distinct species. I send a couple of specimens for 
the University Museum, which may not possess Irish ones. It would be desirable 
to have a comparison of the Succinea Angustior with the British Oblonga made by 
competent judges. 
The Helix Aculeata being a shell rarely met with, it may be useful to state the 
localities in which I have found it, and where, so far as I know, it has not been 
heretofore noticed. About two miles below Mallow, on limestone rocks, on the 
borders of the valley of the Blackwater, I found two dead specimens toge¬ 
ther, under moss, with which the rock was covered. In an hour’s search I could 
not discover another. Many years since, in a beech wood, not far from the Cum¬ 
berland Cave, near Matlock, in Derbyshire, I obtained a single specimen among 
