FORMER LAXD COXXECTIOXS. 321 



niunication : for during one portion of that period (Pliocene), it 

 is known that North America became invaded by animals from 

 Eurasia, including numerous antelopes and other ruminants. 



Again, it is admitted that most of the resemblances visually 

 noted are in animals of which the ancestry is entirely unknown. 

 This is, indeed, a serious objection. It means that any deductions 

 we may make from the facts of present-day distribution have to 

 be regarded inerely as theories. On the other hand, if we restrict 

 ourselves to those animals of which some ancestor is known in 

 fossil form, more than 99 per cent, of our fauna becomes excluded 

 from consideration. The extreme imperfection of the geological 

 record, so far as terrestrial invertebrates are concerned, is particu- 

 larly marked in the southern hemisphere, where nothing 

 comparable to the fossiliferous amber of Europe, nor to the rich 

 shales of Florissant has been found; and in South Africa, even the 

 Tertiary vertebrate fauna is almost unknown.* 



(C) Other recent criticisms are contained in a long and 

 important paper by Dr. John D. Haseman.' He attempts to 

 show on geological grounds that South America has not been 

 connected with the Old World at any period. Thus he rejects 

 the Gondwanaland theory in toto. And yet, to the author him- 

 self, the geological evidence does not seen absolutely prohibitive, 

 for referring to Pilsbry's views in favour of a Brazilian-West 

 African connection, based on a study of land-shells, he says: — 

 There is so much other geological evidence against the building 

 up of a land mass across the great ocean depths of the South' 

 Atlantic, that we may consider Dr. Pilsbry's view highly improb- 

 able, at least until some dynamic and more careful field studies 

 have been made on the non-uiarine mollusca of the regions in 

 question." (Italics mine). 



The author affirms his belief that all the South American 

 animals originally came from North American stock. The evidence 

 of the freshwater fish is dismissed, inasmuch as he regards a 

 certain North American Eocene fossil (Priscacara) as a Cichlid,, 

 and indicating a nortliern origin for that famil3\ However, an 

 authority of much greater experience, Mr. C. T. Eegan, emphati- 

 cally denies this identification, stating that Priscacara actually 

 belongs to the North American Centrarchidae. Dr. Haseman 

 also indicates what he thinks is " another source of error in 

 former interpretations, in ignoring the possibility of similar 

 evolution of the identical ancestral stock in remote but similar 

 environments. " 



Unfortunately, no instances of this are cited, but if it means 

 that Afro-American affinities in any group of animals and Afro- 

 Asiatic differences are explicable as a consequence of resemblances 

 and differences of environment, the principle seems quite imduly 

 extended. 



(D.) Another criticism was contributed by Dr. C. J. Maury 

 at the last meeting of the Association in LourenQO Marques 



* In his '! Rift Valleys anH Geolocry of East Africa." Prof. J. W. Grfigory 

 gives a list of vertebrates known from the Lower Miocene of Karungu Lake. 



