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wishing^ to iind nearly all the different species within 

 the narrow limits of a single pond, exclaims with a 

 rather disappointed air, " I have searched and searched, 

 but cannot find a single Limnoeus pereger. " This, he 

 is told, is by no means an uncommon thing, though the 

 reason is less easily given ; he is also informed, that 

 frequently in the same stream, in one part nearly all 

 shells are of a species difiering from those inhabiting 

 another. At the bottom of one slowly flowing stream, 

 several large bivalves are pointed out to us, sunk 

 almost over-head in mud; these turn out to be Ano- 

 donta Cygnea. With no little eagerness we apply our 

 spoons, but without much effect, except upon those 

 which are tenantless ; looking to our preceptor, who is 

 smiling at our attempts, we entreat him to help us, but 

 he shakes his head, and says we must move on to a 

 part of the stream which is clearer than that we have 

 disturbed. Here we watch him quietly plunge the 

 handle of his spoon into the water, and insert it be- 

 tween the valves of one of these shells, and draw it 

 out again with it firmly attached to the end. 



Our next Conchological excursion, we are informed, 

 is to be confined more particularly to those which in- 

 habit woods, and hedge-rows ; and we set out without 

 any definite idea as to what we are likely to meet with. 

 The first convenient mossy bank is, however, submitted 

 to a search ; down we drop on our knees, pull aside the 

 leaves and stems of the plants, and after diligent search, 

 we find several species, chiefly of the Helix and Zonites 

 tribe ; Pupa umhilicata and also Btdimus ohscurus are 

 added to our stock, though but sparingly. Thence we 

 proceed to a wood of more ancient growth, where the 

 soil, for some depth, is little else than a carbonaceous 



