12 WEST COAST SHELLS 



shell-man, or conchologist, as he is often called, can 

 quickly tell even from a dead shell the probable sur- 

 roundings of its dwelling-place. A novice may 

 make mistakes, even in collecting, for often land 

 shells get washed into rivers and even into the ocean, 

 and may be found where they did not grow; but all 

 this is to be expected and guarded against in the study 

 of shells. The real test is to hnd the animals that 

 make the shells living at home and in natural condi- 

 tions, and then you are sure that they are where they 

 ought to be. And so if you hnd banks of oyster- 

 shells attached to rocks on some hillside you may 

 rightly infer that that part of the country was once 

 under the sea, and not that in olden times oysters 

 went off on picnics to the mountains. 



Sometimes dead shells are found washed up on 

 a beach a long way from the place where they lived, 

 having been brought in a ship's ballast and cast 

 overboard or else scattered from some collection. 

 I once had a shell brought to me for identihcation 

 which the tinder declared he picked up on the Cali- 

 fornia coast, though I am certain that its home was 

 in the Atlantic Ocean. Doubtless he was truthful 

 in his statement, but as the shell was dead the proba- 

 bility was great that some one had accidentally or 

 willfully dropped a foreign shell in the water far 

 from its original home and that the waves had 

 washed it up along with many native shells. If it 

 had been alive the case would have been different. 

 In a much greater degree it is unsafe to buy shells 

 in stores along the seaside with the thought that 

 therefore they are certainly natives of that coast. 



