CHAP. XXII.] MOLLUSCA. 515 



Achatina (87 sp.) is most abundant and finest in the Ethio- 

 pian region, over the whole of which it ranges ; hut there are 

 also species in Florida, the Antilles, the Sandwich Islands, 

 Ceylon and India. The described species are now more than 

 doubled. 



Hyalina (84 sp.) inhabits all Tropical America and the 

 Antilles, North America to Greenland, and Europe to the 

 Arctic regions. Comparatively few new species have been 

 described. 



Cylindrella (83 sp.) inhabits the West Indian islands and 

 Guatemala to Texas, with a sub-genus in the Philippine Islands. 

 Species since described have more than trebled the number in 

 this genus. 



Cionella (67 sp.) is widely scattered ; in India from Ceylon to 

 the Khasia Mountains, Brazil, New Granada, the West Indian 

 islands, Palsearctic, and northern part of Nearctic regions, 

 Pacific Islands, New Zealand, and Juan Fernandez. About 20 

 new species have since been described. 



Glandina (66 sp.), Peru to South Carolina and the Antilles, 

 with three species in Central Africa and one in South Europe. 

 About 40 species have been added to this genus. 



Stenogyra (49 sp.), widely distributed : Tropical America and 

 West Indies to Florida, South and West Africa, the Mediter- 

 ranean region, India and the Philippines. About a dozen new 

 species have been described. 



Succinea (41 sp.), widely scattered in all the regions, and in 

 St. Helena, Juan Fernandez, Tahiti, Chiloe, Greenland, West 

 Africa, Himalayas and Australia. The described species are 

 now more than 100. 



Partula (39 sp.), Solomon Islands to Tahiti and Sandwich 

 Islands. This genus has also been increased to near 100 

 species. 



Streptaxis (34 sp.), most abundant in Tropical South America, 

 but occurs in West Africa, the Seychelles and Eodriguez Islands, 

 Ceylon and Burmah. It now contains over 100 described species. 



Spiraxis (33 sp.), Yucatan to Mexico, and less abundant in the 

 West Indian Islands. About 20 species have been added. 



