OF LANCASTER COUNTY 



oil 



CONCHOLOGY.i 



Although this branch of natural history is of sufficient interest to those engaged in 

 its study to attract the attention of some of the best minds of our country, as well as 

 of other enlightened nations, yet it is one in which the public is usually not much con- 

 cerned, especially not in its scientiiic details. AVaiving entirely tlie .piestion of its 

 usefulness, it is deemed of sufficient importance, to constitute a part of oiir liistoiy of 

 the natural sciences of the county of Lancaster, as it unquestionably does, in tlie great 

 kingdom of nature. So little, however, is known of the individual habits of this clas.s 

 of animals of a practical character; and as a general thing, so little do they interferc 

 with the productions of human industry, that a mere list of the names of what ha.s 

 been found within the boundaries of the county, has been deemed .sufficient on this 

 occasion; and then only of those that are "shell-bearing." It is perhaps hardly ne- 

 cessary to say that Concliology embraces that class of animals usually known under the 

 common name of "shells." So far as the territory of Lancaster county is concerned, 

 they may be divided into Univalves, being composed of a single piece or shell, and 

 Bivalves, composed of two pieces or shells, united together by a sort of hinge, enclosing 

 the animal between or within them. They are also called Fluveatile- Shells, when they 

 inhabit fresh water — the "bivalves" being of this character — iiwd Land-Shells, vihcw 

 they inhabit the land. Part of the "univalves" are fluveatile, and part of them 

 land shells. Shells are also divided into Classes, Sub-classes and Orders, but as the 

 number and variety is too limited in our local couchology to attempt such a classifica- 

 tion, none will be made in that direction. Both land and water shells — or i-ather 

 the animals that occupy them — usually feed on vegetation, such vegetation as is indi- 

 genous to their respectivs elements. The water shells perform, perhaps, a more im- 

 portant function in purifying their native element than they receive credit for; but some 

 of the land shells, have long been considei-ed as destructive to some species of vegeta- 

 tion, and especially to the productions of the "Truck Gardener." 



CLASS MOLLUSCA. 



SHELL BEARING MOLL USCA. 



{UNIVALVES.) 



Fam. Succinid^. 



SUCCIN^. 

 obliqua Say. 

 ovalis Say. 



Fam. Helicellid.e. 

 Suh. Fam. Ilelicellinoe. 

 Macrocyclis. 

 concava Say. 

 Hyalina. 

 *fuliginosa Say. 

 indentata Say. 

 arborea Say. 

 electrina Old. 



Sub-Fam. Gastrodontinse. 

 Mesomphix. 

 ligera Say. 

 CoNULrs. 

 m^inistrisima Say. 



1 Contribute! by Mr. 



Gastrodonta. 



suppressa Say. 

 Strabila. 



labyrinthica Say. 



Suh-Fctm. Patulinx. 

 Angospica. 



alter nata Say. 

 Patula. 



perspectiva Say. 



striatella Ant. 

 IlELicoDiscrs. 



lineata Say. 



Fam. Helicid.e. 

 Sub-Fam. Mesodontse. 

 Vallonia. 



minuata Say. 

 Mesodox. 



thyroides Say. 

 buculenta Old. 

 dentata Var. 

 albolabris Say. 

 H. G. ISruckhart. 



