LAND AND FRESH-WATER MOLLUSCA OF GREENOCK. 283 
observed in truly decollated shells, such as Bulimus_ 
decoliatus. Possibly, however, we may have come 
on them too soon for that to have taken place; or 
perhaps the closing up of the broken end would be 
an after consideration, especially if. it were found 
that there was some danger of an attack being made 
on the animal from behind; or perhaps it was a 
“new departure ’’—an experiment as to the econo- 
mising of space in order to lighten as much as 
possible the burden that had to be carried, so that 
the “struggle for existence” might be engaged in 
with a greater likelihood of success ;—but the work- 
ing out of these abstruse questions I leave to those 
with more subtile intellects. 
Among the rarer species, for which new stations 
are recorded, is Acme lineata, which my son found 
near the Cloch in 1881. In the following year he 
‘found another specimen about the same place, but 
it was partially crushed. Of the species and varieties 
mentioned in the annexed List, the only form which 
I do not possess or have not seen is Zonites purus 
var. margaritacea, for which, in the 1876 list, the 
Cloch is given as a habitat. 
I have to acknowledge my obligation to the late 
Dr. Gwyn Jeffreys for his kindness in identifying 
a few of the rarer and more critical species men- 
tioned in this List. 
The arrangement of the Conchological Society's 
Last of British Land and Fresh-water Mollusca (1883) 
has been generally followed. 
List of Land and Fresh-water Mollusca of Greenock and 
surrounding District. 
CONCHIFERA. 
SPH ARITDA. 
PISIDIUM FONTINALE (Drap.), var. PULCHELLA, Jenyns.—Moss- 
; clave pond, near Greenock. 
PUSILLUM (Gmel.).—Mossclave pond, and other places. 
NITIDUM, Jenyns.—Pools, side of Kilmalcolm road, near 
Port-Glasgow. 
