Over a South Atlantic Continent 443 



and Australia. Mordacia or Caragola mordax occurs 

 in Chile and Tasmania. The writer has already claimed 

 (/: 402) a freshwater origin for the group, even though 

 some are now anadromous or wholly marine. The group 

 is evidently a very ancient one, in fact the writer would 

 claim for it the oldest pedigree of the entire series that we 

 ordinarily call "Fishes." 



The observations by some of the zoologists who studied 

 the material secured by the Transit of Venus expedition in 

 Kerguelen are very valuable. Of the molluscs Smith writes : 

 "The malacological fauna resembles generally that of the 

 Falkland Islands and South Patagonia. More than half 

 of the genera, and seven or eight of the species found at 

 Kerguelen Island are known to occur at those localities," 

 and he adds (p. 168) a comparative table in illustration. 



In his study of the Crustacea Miers writes "Amongst 

 15 indigenous species several are characteristic of the Ant- 

 arctic region, which in its widest sense embraces Tierra del 

 Fuego, the Falklands, and the lands and islands of the 

 Antarctic Ocean. Halicarcimis planatiis and Sphaeroma 

 g'tgas are known to inhabit the seas of Patagonia and New 

 Zealand, and are especially abundant in the former area." 

 He then gives Tierra del Fuego, "the Falklands, abund- 

 ant," Kerguelen, the Auckland Islands, and New Zealand 

 as the range of the former; while for the latter (p. 203) 

 he gives the Falklands (var. lanceoJata) , Kerguelen, Auck- 

 land Islands, New Zealand and Australia. 



Geoffry Smith writes (277 : 216) : "The copepod genus 

 Diaptomus, characteristic of lake plankton, ranges all over 

 the northern hemisphere and into the tropics, but it is al- 

 most entirely replaced in the southern hemisphere by the 

 related but distinct genus Boeckella, which occurs in tem- 

 perate South America, New Zealand and south Australia, 

 and was found by the author to be the chief inhabitant in 

 the highland lakes and tarns of Tasmania, Diaptomus being 

 entirely absent. Then in commenting on the chorology of 

 Niphargiis and Gammarus he says (p. 217) "it seems prob- 

 able that they have reached South Australia by way of 

 South America," and later he adds "the other common 

 freshwater Amphipod in temperate Australia and New 



