6 
small Spondylus, of Perna imhricata and Meleagrina cda- 
perdicis, also of two species of Serpula, and the tube of 
another worm delicately made of the shells of a small 
Anatifa. 
0. multiradiata in happier circumstances develops an 
upper valve of the usual laminated or even flounced charac- 
ter, but in these specimens any trace of such structure has 
been worn away by the waves, and the valve is smoothed 
and polished, and often looks more like a corallinous growth 
than an oyster shell. 
The Spondylus and Chama, though equally affixed, do 
not exhibit this superficial abrasion. Perna and Meleagrina 
are delicately laminated, and even spined; but then they 
are attached only by byssus, and so yielded to shocks upon 
their floating island. 
Mr. Hyde showed some shells of Cyclas rivicola from 
the Marple Canal, and some living specimens of Gyrinus 
marinus. 
Mr. F. Nicholson, F.Z.S., showed skins of, the Ring-ouzel, 
Merula torquata ; the Merlin, Falco cesalon ; and the Com- 
mon Dipper, Cinclus aquaticus; all taken within 12 or 15 
miles of Manchester. 
Mr. H. C. Chadwick, F.RM.S., exhibited under the 
microscopes the following Hydroid Zoophytes. Clytia 
Johnstoni,Aglaopheniapluma,2iXid Eudendrium ramosum; 
this last specimen showing very beautifully the sexual cells 
described by Professor Weisman in ‘^Nature,” Nov. 1883. 
Mr. Cameron exhibited (chiefly from Central America) a 
number of Hymenoptera belonging to different genera, sub- 
families, and even families, which showed a remarkable 
similarity in coloration and markingvSj and consequently 
