Panama Shells. INTRODUCTION. 



beneath stones. Many such heaps were collected in the mass, 

 to be culled over in the leisure of home. To this source we 

 are wholly indebted for many species of shells, not a few of 

 which are in such a good state of preservation that we have 

 to regret only the impossibility of describing the station of 

 these species. 



In these Pacific waters, not much addition to the stores 

 of the collector can be made from the drift shells. Yet the 

 flow of the tides and a moderate surf brought several species 

 within reach. Several of the bivalves, which live buried in 

 sand, and whose station eluded discovery, were thus obtained. 

 But especially were we indebted to this source for the ex- 

 tremely minute species, several of which were not recognised 

 until the conchiferous rubbish and sand had been assorted 

 with sieves and then carefully examined. 



From the natives we obtained but little aid. The shells 

 of a few edible species vveie taken from heaps near their huts. 

 A few species were obtained in a fruit shanty, which was 

 kept by an American on the Plaza. The habitat of most of 

 these was verified by subsequently finding them on the shores. 

 That of four or five species was satisfactorily inferred, inde- 

 pently of the testimony, from the fact that no shells known 

 to inhabit other regions were seen in the shanty, and that 

 these species have been found by others in the same zoologi- 

 cal province. Those which were thus obtained are mentioned 

 accordingly in the statement of habitat. 



In a few instances it will be noticed that our account of 

 the station differs somewhat from Mr. Coming's. This is due 

 chieily to the considerable range which some species have, 

 especially with different circumstances of place. Thus sever- 

 al of the species, which we found at the low water mark of 

 spring titles, were obtained by Mr. Cuming at the depth of 

 fifteen or more fathoms. The difference between such sta- 

 tions is obviously of much less importance than that between 



