398 MAKUAL OF THE MOLLUSCA. 



Helix 13 Tornatellina 6 Cyclopliorns 5' 



Naaina -18 Pupa 3 Omplialotropis 6; 



Bulimus 1 Succinea 12 Helicina 13 : 



Partula 15 Electrina 1 



The fluviatile shells are species of P//j/m, 3Ielama, Jssiminea {Taheitana), ■ 

 Neritina, and Navicella ; the two last heiug often literal, or even marine in j 



their habit. ] 



Low Coral-islands. | 



The Atolls, or lagoon-islands, are less prolific ; 2 Helices, and 2 Partula ] 

 are found at Oualan, in the Caroline Archipelago; and from Chain Island \ 

 {Annaa), the centre of commerce in the eastern Archipelago, have > 

 been ohtomedi.—HeUx 2 s\i., Nanina 1, Particia ^ , Tornatellina 1, Cyclo- \ 

 phorus 1, and Melampv.s nmcronatus . j 



Sandwich Islands. j 



The land shells of these islands exceed 100, and are all, or nearly all, \ 

 peculiar: there is one Lirnax ; and in the fresh -waters are found Lijnnaa \ 

 volutah-ix, Fhysa reticulata (Gould), Nerltopsis'^ Neritina Nuttalli and \ 

 undata, and TJnio contradens (Lea). ; 



In the I. Kani, two species of ^c/^ajfe^fl; have been found ; the Achatinella j 

 are elongated {Leptachatina, G.) and the Helices planorboid and multispiral. \ 

 In Molokai the Achatinellse are large and coloured. In ]\Iaui and Oahu j 

 the Helices are small and glabrous, or hispid, ribbed and toothed. In > 

 Hawaii, Snccineas prevail, and Achatinellae are rare. — {Gotild). j 



Helix 13 Achatina 3 Papa 2 J 



Naniiia 4 Achatinella o(j Yitrina 2 i 



Bulimus 5 Tornatellina 3 Succinea 10 ^ 



Partula 4 Balea 1 Helicina 6,' 



The Island of Guam, Ladrones, has 3 sp. of Partula, 2 of Achatinella, \ 



and 1 Omplialotropis. At the Marquesas have been found 3 sp. of Nanina, 



1 Partula and 1 Helicina. \ 



NEW WORLD. j 



16. Canadian Region. j 



The country drained by the Great Lakes and the river St. Lawrence j 

 possesses very few peculiar shells, and these mostly of fresh-water genera. It I 

 is chiefly remarkable for the presence of a few European species, which | 

 strengthen the evidence before alluded to (p. 358.) of a land-way across the j 

 north Atlantic having remained till after the epoch of the existing animals j 

 and plants.* 



* For example, the common Heather {Calluna vulgaris), one of the most abun- 

 dant social plants of Europe, characteristic of the moorland zone, and seldom rising ■ 

 above 3000 feet on the mountains of Scotland.— (JFff^sora.) According to Pallas it: 

 abounds on the western flanks of the Ural Mountains, but disappears on their eastern : 

 side and is not found in Siberia. In the Pliocene period it appears to have spread 

 itself nothward and westward to Iceland, Greenland and Newfoundland, wliere it still j 

 grows, the only heath indigenous to the New World. — (Humboldt.) 



