HOW TO PRESERVE A COLLECTION 



On the Monday evening following our visit to the museum, we met at 

 the home of Professor Parker to help him sort and preserve some collec- 

 tions which he had made several days before. His work-room was large 

 and airy, provided with running water and a good sink ; the tables were 

 covered with pans, bottles, files, tweezers of various sizes, an alcohol lamp, 

 and a compound microscope. The aquarium which had so interested us 

 on a previous visit, was placed near the window, and on the opposite side 

 of the room was a large bookcase filled with books on conchology, birds, 

 and other branches of natural history. 



The Professor greeted us cordially, and immediately set us at work. 

 We first separated the clams from the snails, and placed them in differ- 

 ent pans of water, after which we proceeded to extract the animal from 

 the clam shells. This we did by placing the shells in lukewarm water, and 

 then heating the water to the boiling-point. This killed the animal, and 

 made the valves of the shell separate. The boiling water also prevented 

 the epidermis from cracking. Professor Parker told us that it was always 

 better to place the shells in lukewarm water at first, in order not to crack 

 delicate shells, and also to preserve the natural gloss. The adductor mus- 

 cles were next cut, and then the animal was easily removed from the shell. 



After cleaning the clams in this manner, we washed them thoroughly 

 under the faucet, and then tied the valves together in their natural posi- 

 tion. The Professor cautioned us to be very careful in cleaning the shells, 

 in order not to injure the ligaments. We were told to grease the outside 

 of the shell with vaseline, which would aid in keeping the epidermis from 

 cracking. After greasing them thoroughly and rubbing the vaseline in with 

 a flannel cloth, we removed all surplus grease, so that the shells might not 

 feel sticky. We then placed all of the shells in rows on boards and put 

 them aw T ay on a long shelf to dry. 



In one of the clam shells which George had opened he found a little, 

 round, pearly object, and he asked Professor Parker what it was. <k That,' 1 

 said the Professor, " would have been a rather nice pearl if it had not 

 been boiled. These pearls are frequently found in our fresh-water 

 bivalves, and are caused by some irritating substance becoming lodged 

 in the soft part of the animal. This forms a nucleus which the clam 



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