284 ON (10LLKCTIN(i SHELLS. 



da}' or two, then take them out, dry and assort them, and put 

 them in their proper receptacles. But Pupas, Vertigos, and the 

 small Helices are generally dirty. They ma}' be perfectly 

 cleaned in the following simple manner : 



Put all you have of one species into the test tube. Put in 

 with them a small quantity of the clean sand-, saj'- one-fourth 

 or one-fifth Avliat the tube will contain. Fill it with water, and 

 shake very gently. As the sand removes the dirt, turn out the 

 dirt}^ water and fill with clean. In a few moments judicious care 

 will clean such shells perfectly, and not damage them in the 

 least. When clean, turn water, sand and all into a saucer, put 

 in a little more water, shake all gently, and the sand will go to 

 the bottom, while the little concentric wavelets will gather all 

 the shells into a small space in the centre, whence they may. be 

 removed with a spoon or au}^ convenient instrument. Pour off 

 the water, dry your sand and put it away for future use. Never 

 use any acid or oil about land shells^ unless the tiniest amount of 

 the latter on the too often eroded apices of burrowing species. 

 Remember this caution, and always act upon it. Each species 

 when cleaned and thoroughly dried should be accurately labeled 

 with name, author, localit}^, and date of capture — if the locality 

 is one seldom visited. The little boxes or tubes containing the 

 smaller species should be kept in a larger box, the Pupas together, 

 Vertigos together, etc. This will reduce the labor of selecting 

 exchanges more than one-half. 



Fresh-water Shells. The following implements are needed : 

 Brushes, as before, but one or two larger and stitfer ones for the 

 Unionidse. 



A scoop made of wire gauze, fine enough to hold the smallest 

 shells, with a socket for the handle. This scoop should be hemi- 

 spherical, eight inches in diameter, with the rim made of good, 

 tough hoop iron, to which the socket is attached. 



The handle may be used for a walking-stick, and the scoop can 

 be carried in your basket. Both socket and handle must have 

 a hole for the spring-key. A quart or two of saturated solution 

 of oxalic acid. A small quantity of nitric acid. A bottle of 

 boiled linseed oil. Bottles of alcohol, diluted somewhat, say 

 one-fourth water. A few tin boxes of various sizes. These are 

 all the necessary tools; 



Having reached your locality, if the bottom is mudd}'', or 

 sandy, and you are seeking for Sphaerium, Pisidium, the Amni- 

 colidse, etc., usually found in such stations, put your handle into 

 the scoop, slip the spring-key into its place, and scoop up mud, 

 sand and shells, by a dragging motion aloug the surface. AVhen 

 the scoop is sufficientl}^ filled, shake it in the M'ater, washing out 

 the mud and finer sand. Pick out the sticks and leaves, and 

 continue this operation until A'our shells are easily removed. 



