ON COLLECTING SHELLS. 211 



meiitioued what are the prospects of our ever becoming acquainted 

 with all the inhabitants of the deep throughout the globe I " 



Equalh^ important results, have attended the more recent 

 dredging operations of the United States Fish Commission's 

 Fish Hawk, southeast of Rhode Island, adding several hundred 

 species to our fauna. 



The reader of these pages, if possessed of a salt-water aqua- 

 rium, is earnestly recommended to stud}- marine mollusks in the 

 living state. A judicious observer will not only derive much 

 pleasure thereby, but may also contribute to our knowledge of 

 the habits of these interesting animals. But few of the species 

 have been intelligentlj' studied in this manner, and it is almost 

 certain that very much is to be learned by the use of this method 

 of investigation. 



Land and Fresh-water Shells. The following directions for 

 collecting and preserving these, are principally compiled from 

 papers by Prof. A. Gr. Wetherby (Jour. Cincin. Soc. Nat. Hist.), 

 and Dr. James Lewis (Smithsonian Report, 1866). 



Before the (::ollector can enter the field with much certaint}'^ as 

 to the anticipated result of his labors, it may be necessary for 

 him to satisfy himself that there are in the district about him 

 shells enough to offer encouragement. It will be found generally, 

 that those sections of the countr}^ that have a dry sandy soil are 

 unfavorable to the production of mollusks. Regions in which 

 pines abound are proverbially of this character, and here the 

 efforts of the collector are usually but indifferently rewarded. 

 In the moist alluvial soil of limestone formations are found the 

 most favorable conditions for the production of mollusks. This 

 is more notably true with regard to hind shells ; aquatic species 

 are also affected similarly, but less conspicuously, by the character 

 of the soil. But it w^ill almost invariably be observed that waters 

 deficient in lime do not produce shells as perfect nor in as great 

 numbers as waters charged with that earth. 



Land Shells. With a few exceptions, relating to some of the 

 smaller species and also a few species of semiaquatic habits, the 

 land shells of this countr^^ are found most abundantl}'^ in the 

 wooded alluvial regions, especially upon hill-sides having a 

 northern exposure; where, during the day they are concealed 

 under fragments of fallen trees, bits of bark, chips, etc., some- 

 times under leaves or in the tufts of rank growths of moss. 

 Some species will be occasionall}^ found in the moist debris of 

 shaly rocks in ravines. Species peculiar to the Southern States 

 are sometimes met with on shrubs and trees. Some species of 

 semiaqu^atic habits, though occasionally seen on the rank vege- 

 tation along rivers (sometimes several feet from the ground), 

 are more frequently observed under bits of wood, leaves, etc., 

 near the mudd}' slopes of streams or ponds, or in the vicinity of 



