260 FORMATION OF A LINCOLNSHIRE NATURALISTS’ UNION. 
An examination of the water-weeds and caddis-cases requires 
time and patience, but the trouble so expended has often its reward. 
The caddis-cases particularly form a very profitable study; the 
curious animal which you will invariably find in them is a veritable 
conchologist, for it collects the shells of the pond or dyke and glues 
em together, forming for itself an almost invulnerable stronghold 
in which it resides. It was to one of these cases we were unquestion- 
ably indebted for directing our attention to a more careful sorting of 
the water-weeds for that rare freshwater mollusc Segmentina nitida 
(Mull.), of which we caenhom obtained several living specimens. 
Lastly, in regard to the aquatic molluscs, we observed several 
instances of abnormal ane Planorbis umbiticatus, which is 
particularly common near Saltfleetby, appears to affect in many 
specimens a very striking swollen character near the mouth of the 
shell. One specimen of this species exhibited a very odd shape; 
the shell had apparently received some injury at one time, resulting 
in the interference of the growth of the whorls on the normal plane. 
A specimen of P. vortex was taken with the whorls very much 
disjointed, giving the shell a distinct conical appearance. In both 
cases the shells contained the living animal, which remained perfectly 
lively and well in the jars of water in which ved were placed for 
subsequent observation. 
The following aquatic species were taken on eh route :—/isidium 
pusillum, Spherium corneum, Valvata cristata, Bythinia leachii, 
. tentaculata, Viviparus contectus, Limnea palustris, L. stagnalis, — 
Ps peregra, Physa fontinalis, Planorbis contortus, P. corneus, £- 
umbilicatus, P. carinatus, P. vortex, and Segmentina nitida. = 
The weather had been much too dry to have made search for 
terrestrial mollusca successful, even had we had time on our hands 
me have doneso. The Rev. C. W. Whistler had succeeded in obtaining 
specimen of Hyalinia fulva, and on the previous day Mr. J.Coe 
(Hull) collected on the coast near Mablethorpe the shells of Helix 
aspersa var. exalbida. H. caperata was noticed on the coast. The 
broken shells of Helix nemoralis were fairly abundant on the sand-— 
dunes, where they appear to have met their unhappy fate through 
some enterprising members of the feathered tribe. 7S 
Mr. John Cordeaux, M.B.O.U., gives the following as a list 
) of the birds seen at Mablethorpe, on June 12th, and the two ene a 
ft ing ore with nes notes on some of the species:— oe. 
