PERIPATUS IN SOUTH AMERICA 
347 
members of the Andean group. This discontinuous distribu¬ 
tion is a very noteworthy fact, for it cannot be explained by 
the supposition that some member of this Andean group may 
still exist and have been overlooked in the intermediate vast 
tract of country, because many specimens of Peripatus have 
been discovered in Costa Rica, Nicaragua and Panama, all 
belonging to the Caribbean group. Accidental dispersal, such 
as marine currents, cannot be invoked as being responsible for 
this distribution. It is due, in my opinion, to a former direct 
land connection between western Mexico or Guatemala and 
some part of the west coast of South America. That the 
mountain system of Guatemala suddenly terminates at the 
edge of the Pacific, and that it formerly had a westward 
continuation, has been alluded to, and I have mentioned also 
several cases of discontinuous distribution that I thought 
were due to the existence of an ancient land, more or less in¬ 
dependent of Central America. The newt Spelerpes is one 
of these. Its headquarters seem to be in Mexico. A few occur 
in Guatemala, Costa Rica and Chiriqui. Further south we 
meet with the genus again in Colombia, Ecuador and northern 
Peru, but nowhere else in South America. The tortoise 
C-helydra rosignoni occurs in Guatemala. It is absent from 
the rest of Central America, yet in Ecuador we find an isolated 
colony. Another tortoise, Geoemyda punctularia, inhabits 
Guatemala and Mexico. Southward it is only known from 
Ecuador, Colombia, Venezuela and further east. The gecko¬ 
like genus Eublepharus is probably an exceedingly ancient 
one, its range being most peculiar and strikingly western. 
One species occurs in California, another in Mexico, still 
another in Panama, and lastly one in Ecuador. All the re¬ 
maining species, which show great resemblance to the 
American ones, are confined to southern Asia. We probably 
have to deal in this case with a persistent type which through¬ 
out many geological periods has retained the same characters 
and has died out in the still existing land fragments of the 
ancient Pacific continent, whence it originally spread east 
and west after its subsidence. There are numerous other 
examples, particularly among plants, implying that the land 
which I described as lying westward of Central America 
once touched the South American continent, probably near 
