SOME INDIAN FRESHWATER SHELLS. 93 



simple enough as soon as the eye has become accustomed to the refraction due 

 to the surface of the water, has the advantage of not stirring up the mud, 

 so that the water remains clear and other specimens are obtainable at the same 

 spot. c 



All specimens should if possible be collected alive, dead and worn ones be- 

 ing of little or no value. They should then be plunged into lolling water; this 

 causes instant death to the animal which may then be removed in the case of 

 bivalves by the aid of a small blade and univalves by a stout pin. It will often 

 be noticed that many shells have on them a green slimy growth. This to a 

 great extent may be removed by careful brushing with an old tooth-brush and 

 plenty of hot water. Some collectors however prefer to leave this growth. 

 All that is now necessary is to set aside the shells to thoroughly dry. Bivalves 

 after the death of the animal are apt to gape apart. The two valves must 

 be drawn together by binding cotton round and tightly securing, and the 

 cotton should not be removed for some days allowing the ligaments of the 

 shell to thoroughly dry. For very small bivalves where binding is not possible 

 a strong cement should be used. Many of the univalves as Vivipara and 

 Ampullaria have a horny covering (operculum) at the mouth of the shell. As 

 this adds to the value of the specimen it should be carefully removed from 

 the animal and placed in its natural position within the mouth of the shell 

 with a little cement on a plug of cotton wool. 



Arrangement of a Collection. 



For the display of a collection of shells a cabinet is the best medium, the 

 drawers being divided into a number of partitions of different sizes. The 

 larger specimens are then laid on cottonwool placed in the divisions. For 

 smaller and more delicate specimens glass top boxes are very nice and help 

 considerably to give more show to a collection. Every specimen should of 

 course be labelled as recommended below. As many of us in India, however, 

 have no settled abode and are liable to be transferred at a moment's notice, a 

 cabinet becomes somewhat of a nuisance in transit and unless specimens are 

 securely packed they are likely 10 get broken. For my own part I much prefer 

 to have all my shells in chip or pill boxes. Very useful boxes for the storage 

 of specimens are sold by most dealers and known as " purple shouldered" boxes. 

 These are nested and are of various sizes, the most useful all round size 

 being 2" in diameter. They are in every way vastly superior to the ordinary 

 chip box, being made of stout cardboard and much stronger. These boxes, 

 together with the specimens they contain, are easily packed into quite a small 

 space and there is no risk of breakage during a journey. The boxes have 

 white tops to the lids. On this should be written the name of the shell, 

 locality, date, and name of collector. A corresponding ticket should accom- 

 pany each shell inside the box. It is also important to add one or two other 

 items such as altitude, whether found in a small pond, stream, river, or lake, 

 and any other detail that may strike the collector. 



* Latter. Natural History of Common Animals. 



