412 A ZOOGEOGRAPHIC SCHEME FOR THE MID-PACIFIC, 



Dr. Baur in continuation of his argument has pointed out that 

 " Poci/lojjora, a coral of the Madreporaria, is found only in the 

 Indo-Pacific region. It is represented by an extraordinary large 

 number of forms reaching north to the Loo Choo and Sandwich 

 Islands, and is also common on the west coast of America. It is 

 totally absent, however, from the Carribbean or West Indian Sea 

 and the eastern American coral region. . . . The general 

 distribution of Pocillopoi'a and the Trapeziidaj in the Indo-Pacitic 

 region can only be explained by a former land connection of this 

 region. ... If we consider the Pacific Islands as the remains 

 of a former Pacific Continent, we have no difficulty whatever in 

 explaining the general distribution of PociUopora.^'^' 



In this deduction Baur failed to remember Darwin's caution — 

 " How ignorant we are with respect to the many curious means 

 of occasional transport." Though it was hardly to be anticipated 

 that the problem could be so neatly solved, we can demonstrate 

 in the case of this identical genus how fallacious is the support 

 which Pocillopm'a appears to give to the hypothetical former 

 Pacific Continent. 



Kent collected on Cairn Cross Beach, Barrier Reef, Queensland, 

 " a rounded lump of pumice stone, about 3| inches in diameter, 

 to which two young coralla of the madrepore, PociUopora dami- 

 cornis, were attached. The bases of the coralla are each about 

 \}f inch wide, and the rudimentary tuberculate branchlets are 

 about I of an inch high. This specimen was thrown on the beach 

 in a buoyant condition, as is evident by its still floating lightly 

 even in fresh water. The attached PociUopora probably represent 

 the growth of a few months only, and would, at an early date, 

 have completely invested the pumice stone fulcrum, and caused it 

 to sink."t 



The beaches of Eastern Australia are bestrewn with flotsam 

 from the West Pacific Archipehigoes, including South Sea canoes, 



* Baur, loc. cif. p. S64. 

 t Kent—The Great Barrier Reef of Australia, 1893, p. 122. 



