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earlier developed species intermingling with the rear of their 

 retreating predecessors. 



Although the Epiphallogona have representative species 

 which linger behind and are still to be found in Japan and 

 neighbouring regions, yet their metropolis at the present day 

 is the equatorial islands of the Indo-Malayan region and the 

 adjacent Australian continent : the earlier developed and most 

 primitive species always extend beyond their later developed 

 and more highly organised congeners. 



In America, they preceded the Euadeniate race, by whom 

 they have been dri\-en towards the south, so that at the present 

 time they inhabit Central America, the whole of the West 

 Indian Islands, and Northern South America, often minghng 

 with the competitive and more dominant Euadenia, but ex- 

 tending beyond them on all sides except along the route by 

 which the newer and stronger race are advancing. 



The Protogona are the most simply organised and the earliest 

 evolved of the true Helices, and in their far-off day were the 

 predominant type of the family in the world. They were 

 probably evolved in the same area as the races already con- 

 sidered, but have in process of time spread over almost e\ery 

 part of the habitable world, but are now entirely and com- 

 pletely expelled from the Palaearctic region, by the several 

 series of more advanced forms which successively followed 

 them, so that they now exist only in the most remote and 

 distant regions, their chief asylums being the countries farthest 

 removed and most difficult of access from their place of origin, 

 as the southern extremities of Africa, South America, Australia, 

 Tasmania, and the more remote equatorial islands of Australasia, 

 but they are closely pressed, and their rear overlapped by their 

 Epiphallogonous successors. 



The Protogona are, however, still the dominant and must 

 highly organised race of Hehces in the Eastern United States, 

 being shielded from the intrusion and competition of the more 

 highly organised Euadeniates of the Pacific slope by the inter- 

 vening mountain ranges and desert regions, the Alleghanian 

 plains being thus comparable to the countries and regions already 

 mentioned as harboiu'ing these primitive species. 



Still lower in the scale of life are the more generalised species, 



