358 THK CLASSICAL TRADITION 



been found as fossils. The great classificatory groups are 

 almost as distinct in early fossiliferous strata as they are at 

 the present day. As Deperet says in his admirable book, 1 in 

 the course of a presentation of the matured views of the 

 great Karl von Zittel, " We cannot forget that there exist 

 a vast number of organisms which are not connected by any 

 intermediate links, and that the relations between the great 

 divisions of the animal and vegetable kingdoms are much 

 less close than the theory [of evolution] demands. Even 

 the Archajopteryx, the discovery of which made so much 

 stir and appeared to establish a genetic relation between 

 classes so distinct as Birds and Reptiles, fills up the gap 

 only imperfectly, and does not indicate the point of bifurca- 

 tion of these two classes. Intermediate links are lacking 

 between Amphibia and Reptiles. Mammals, too, occupy an 

 isolated position, and no zoologist can deny that they are 

 clearly demarcated from other Vertebrates ; indeed, no fossil 

 mammal is certainly known which comes nearer to the 

 lower Vertebrates than does Ornithorhynchus at the present 

 day "(p. 115). 



To take a parallel from the Invertebrata, B. B. Wood- 

 ward,- after discussing the phylogcny of the Mollusca as 

 worked out by the morphologists and comparing it with 

 the probable actual course of the evolution of the group, as 

 evidenced by fossil shells, sums up as follows : " The lacuna,' 

 in our knowledge of the interrelationships of the members 

 of the various families and orders of Mollusca are slight, 

 however, compared with the blank caused by the total 

 absence from paheontological history of any hint of passage 

 forms between the classes themselves, or between the 

 Mollusca and their nearest allies. Nor is this hiatus confined 

 to the Molluscan phylum ; it is the same for all branches of 

 the animal kingdom. There is circumstantial evidence that 

 transitional forms must have existed, but of actual proof 

 none whatever. All the classes of Mollusca appear fully 

 Hedged, as it were. No form has as yet been discovered of 

 which it could be said that it in any way approached the 



1 Lcs Transformations du Monde animal^ 1'aris, 1907. 

 - " Malacology versus Palaeoconchology," I 1 roc. Malacological Soc., 

 viii., pp. 66-83, 1908. 



