XI MADAGASCAR 335 



time much more widely distributed. Endodonta (an essentially 

 insular form, like Omphalotropis) actually occurs on Fernando 

 Noronha, off the Brazil coast, and we shall see how an Indian 

 and even a Polynesian element is present off the eastern coasts 

 of Africa. 



Ascension I. — One indigenous species, a so-called Limax^ is 

 all that has ever been discovered. 



(3) The Malagasy Sub-region includes Madagascar with its 

 attendant satellites Bourbon, Mauritius, and Rodriguez, and the 

 Seychelles and Comoro groups. No land Mollusca are known 

 from the Amirantes, the Chagos, or from Aldabra. The special 

 characteristics of the sub-region are the great development of the 

 carnivorous land Mollusca (^Ennea^ G-ibbus'), the occurrence of a 

 considerable number of true Helicidae of great size and beauty, 

 and the prominence of the genus Cyclostoma. 



(a) The Madagascan Province. — The land Mollusca of Mada- 

 gascar, although as yet imperfectly known, possess a striking 

 individuality. Two of the chief characteristics of the Ethiopian 

 region are the paucity of its land operculate and of its Helix 

 fauna ; Madagascar is especially distinguished by the rich develop- 

 ment of both these groups. For size, colouring, and beauty of 

 shape, the Helicidae of the two sub-genera Ampelita and Helico- 

 phanta rival, if they do not surpass, any in the world. They 

 are quite peculiar to this sub-region, not a trace of them occur- 

 ring on the Mascarenes, Seychelles, or even on the Comoros. 

 Helicophanta is distinguished by the enormous size of its embry- 

 onic shell, which persists in the adult (Fig. 223), and in this 

 respect the group appears to be related to Acavus (Ceylon, Fig. 

 204) and Panda (N.E. Australia). As is usual when Helix is 

 well developed, Nanina (about 12 sp.) is proportionately scanty. 



The African Bulimini (^Pachnodus and Pachis^ are repre- 

 sented by two species, but Achatina^ so abundant on the main- 

 land, is scarce. Two other groups of Buliminus, Leucotaenia 

 and Clavator, are peculiar. The presence of a single Kaliella, 

 specifically identical with a common Indian form, is very 

 remarkable. 



Cyclostoma proper, of which Madagascar is the metropolis, 

 is richly developed (54 sp.). Many of the species are of great 

 size and of striking beauty of ornamentation. Unlike its Heli- 

 cidae, this genus is not restricted to Madagascar ; several species 



