OF CONCHOLOGT. 141 



1. Cuba, the Isle of Pines, the Bahamas, and Bermudas. — 

 There is no operculated genus peculiar to this group, except- 

 ing Diplopoma, of which the only species is in Cuba. The 

 single insular representative of the Mexican genus Schasicheila 

 is in New Providence. Two Cuban species only are found on 

 the Continent, Chondropoma dentatum, Say, and Helicina sub- 

 globulosa, Poey, both also in Florida or the adjacent keys. 



The known species of Truncatella, having strictly terrestrial 

 habits, placed by Pfeiffer in the section Montanse, as distin- 

 guished from Littoral.es, are peculiar to Cuba and Jamaica. 



Exclusive of Truncatella, there is no operculated species 

 common to this and any other of the sub-provinces, excepting 

 Helicina rugosa, Pf., found also in Haiti. Meyalomastoma 

 procer, Poey, and Chondropoma dissolution, Pf., are in Cuba 

 and the Isle of Pines. 



The absence of Geomelania and Chittya, and of Stoastoma 

 and Lucidella (all unrepresented on the Continent), with the 

 great development of Megalomastoma, Choanopoma, Ctenopoma, 

 Cistula, Chondropoma, Trochatella, and Helicina, as compared 

 with other sub-provinces, is remarkable. 



The foramen in the superior margin of, and within the aper- 

 ture of many species of Choanopoma, Ctenopoma, Tudora, Cis- 

 tula, and Chondropoma, and the tubercle, especially in Cteno- 

 poma, belonging to this sub-province, are local peculiarities 

 not found, even in species of the same genera, in any other 

 island. (Poey, Memorias, ii. 40.) 



2. Jamaica. — The operculated genera peculiar to this sub- 

 province are Geomela nia and Chittya, and Jamaicea. Stoastoma, 

 with 80 species, represented in Haiti and Porto Rico by one 

 species in each, and Lucidella, with one only in Haati, may 

 almost likewise be termed peculiar. There is no species com- 

 mon to Jamaica and the Continent, and one only found in 

 another island, viz., Cistula lugubris, Pf., which inhabits An- 

 guilla, in the Porto Rico sub-province. Megalomastoma and 

 Chondropoma, both having species on the Continent, and Li- 

 cina, three genera represented in Cuba and Haiti, and the two 

 first in Porto Rico, are not found in Jamaica, while of Cyclotus, 

 which is South American as regards the Continent, it has 34 

 of the 41 insular species. In Jamaica there are 5 genera not 

 represented in Cuba, while in the latter there are 4 not in the 

 former. In every point of view, the operculated land shell 

 fauna of Jamaica appears to be the most varied and peculiar. 



3. Haiti. — This island has no peculiar operculated genus, 

 and no species common to it and the Continent. Helicina ru- 

 gosa, Pf, and Tudora pupdeformis, Sowb., are alone found in 

 any other sub-province — the one in Cuba and the other in 

 Anguilla. Having representatives of Megalomastoma, Licina, 



