34 The Shell-Collector’s Handbook. 
Water-shells, on the other hand, will have to be 
obtained partly with your fingers, and partly with a 
water-net and dredge. Water-weeds, brought to the 
bank by means of a stick, can be examined with the 
hand at the time, or taken home in bags for examina- 
tion at an early leisure. The net will be serviceable 
in sweeping the surface of the pond for any floating 
specimens, and for the detachment of any shells which 
may be attached to the water-plants that are too 
firmly rooted to allow the collector to drag them to 
the shore with his stick. The net I generally use is 
made of strong book-muslin, of an oblong bag-shape,, 
attached to a galvanized iron-ring, which is inserted 
into a long, but withal wieldable, handle. 
The dredge is useful for making an examination of the 
bed of the pond or river for Unios and Anodons in 
particular. It may be obtained from any seller of 
natural-history wares, or made by the collector him- 
self. The best form of this apparatus is the one with 
a square iron frame, having a small-meshed net 
behind, and from the four angles of which ropes are 
attached in such a manner that, at some distance 
from the dredge, they all end equally at one point, 
from which point a single rope extends to the hand of 
the collector. The dredge should be so weighted as 
to enable it to slide along the bed of the pond without 
tilting over its contents. 
When you have arrived at your home after a day’s 
collecting, the shells obtained should be instantly— 
and on that day—killed by means of boiling water, 
and the animals extracted. In the case of univalves, 
this extraction is made by the employment of bent 
