Bd VI: 4) THE ECHINOIDEA. 103 



after the Cretaceous period — and not between South Africa and the Kerguelen 

 group either. That there has been a land connection between South America and 

 Africa I do not venture to deny (though I must still maintain that the occurrence 

 of identical species of Echinoderms, having pelagic larvae, on both the African and 

 the Brazilian-West Indian Coast is no proof of such a connection, as these larvae 

 certainly can pass from one coast to the other 1 ; with the Mollusc larvae the case 

 seems different, as they would probably not be able to cross the Atlantic). But if 

 such a land connection between Brazil and Africa, an Archhelenis-bridge, has existed, 

 it seems evident from the Echinoid fauna of South Africa that this bridge cannot 

 have been situated so far south along Africa as supposed by Ihering; and even if 

 we suppose that it had gone only to Guinea, I do not see the reason, why we 

 have no interrelation at all between these two faunas. The Echinoid fauna of South 

 Africa, in fact, bears evidence against this region having ever, since the Cretaceous 

 period, been in any connection with the South American region, either through an 

 antarctic or, through an »Archhelenis» land-bridge. — It is true that some species of 

 Echinoids are recorded as occurring both in the Patagonian region of South America 

 and at Africa, viz. Austrocidaris canaliculata, Arbacia Dufresnii and Schizaster 

 (Tripylaster) Philippii; but these indications all rest on wrong identifications, as has 

 been shown in the present work (p. 19, 31, 91). 



How we are to reconcile the two contradictory statements: the Patagonian fauna 

 bearing evidence for, the South African fauna against the land connection I will not 

 try to explain. To suggest that the land -bridge had gone only to Guinea would 

 certainly not give a satisfactory explanation; to suppose that the Atlantic continua- 

 tion from »Archibrazil» had not reached Africa, would perhaps reconcile the two 

 contradictory statements in a somewhat better way — but I cannot here enter on 

 this great problem, I only want to indicate, what must be concluded from the study 

 of the Echinoid faunas of these regions, the Echinoids being a group of animals 

 whose importance for zoogeographical studies is certainly very great. 



One thing I would still point out. It appears that the bathymetrical facts known 

 from the Antarctic Ocean are in full accordance with the zoogeographical conclusions 

 drawn from the study of the Echinoids of this region; the latter point towards a 

 former connection between South America and the Kerguelen group, as also with 

 the Antarctic Continent, while the Falkland Islands and South Georgia must be con- 

 cluded to have been in much more recent connection with South America. The 

 map of the Antarctic Sea constructed by BRUCE 2 indicates, in fact, a ridge con- 



1 Cf. Stanley Gardiner, Notes and Observations on the Distribution of the Larvse of Marine Ani- 

 mals. Anm. Mag. Nat. Hist. 7 ser. XIV. 1904, p. 403. 



2 William S. Bruce, Some results of the Scottish National Antarctic Expedition. Scottish Geograph. 

 Magaz. Vol. XXI, 1905. 



