307 



exhibited by P. fontinalis. If such be held to be of taxonomic 

 value, the species Physa gyrina Say could be classified under two 

 subgeneric headings, as forms of this species, even from a single 

 locality, exhibit both a dull and shining surface, due to the 

 presence or absence of sculpture. This is also true of several 

 other American species. With our present knowledge of these 

 forms it seems best to relegate this name to the synonymy of 

 Physa. If, .however, the American forms must be placed in a 

 different genus from the European for no other reason than that 

 they happen to occupy two different continents, the name 

 Alampetis would replace Phy sella Baker as it has twenty-six 

 years' priority. The names would then stand as follows: 



Alampetis v. Martens 1898, synonym of Physa Drap. 

 Petrophysa Pilsbry 1925, as a subgenus, type P. zionis Pilsbry. 

 Physella Baker 1926, synonym of Physa Drap. 

 Phy sella Haldeman 1843, as a subgenus, type P. glohosa Hald. 

 Physodon Baker 1926, synonym of Physa Drap. 

 Physodon Haldeman 1843, synonym of Physa Drap. 



F. C. Baker (1928, p. 408) has stated in very broad terms the 

 distribution of the family Physidae as follows: 'Distribution: 

 North America, Europe, Asia, East Indies, Africa, Madagascar, 

 New Caledonia, Australia.' 



Chamberlin and Jones (1929, p. 158) in their descriptive 

 catalogue of Utah moUusks evidently obtained their information 

 from Baker by stating the distribution of Physidae as follows: 

 'A nearly cosmopolitan family absent, liowever, from South 

 America.' 



It is exceedingly unfortunate that the above statements are on 

 published record. Such general remarks are copied by zoo- 

 geographers and incorporated into papers dealing with the 

 distribution of animals and inferences drawn which are not in 

 accord with the facts. Representatives of Physidae are known 

 from North America, Central America, South America, and the 

 West Indies. They are also common in Europe and are possibly 

 found across northern Asia. They are entirely absent from 

 southern Asia, the East Indies, Madagascar, New Caledonia, 

 and Austraha. In Africa they are limited to the northern part, 



