Horváth Géza (szerk.): A Magyar Természettudományi Múzeum évkönyve 16. (Budapest 1918)

Fejérváry, G.J.: Contributions to a Monography on fossil Varanidae and on Megalanidae 16

Hojmanni KOG. of Stätzling was also most undoubtedly a Varanus, it appears most natural that in the preceding period a genus presenting the characters of to-day must already have existed within a systematic unit which in the Oligocène could not well have denied its under Miocene specialized form.

1 For the above reasons I believe full satisfaction may be given to the requirements of modern system and phylogeny by synonymizing, as happened with the recent Hydrosaurus and PsamniGthe question. DE STEFANO'S words : «tutta l'epoca oligocenica» might also easily allow a slight retrogression in the upper Eocene; and as mentioned above he likewise alludes to the possibility of the under Miocene being here taken into consideration, whilst categorically denying the same for the Eocene ; and though allowing (p. 386) that certain individuals of the fauna, numerous Creodonta for instance, most decidedly remove the age of the Quercy fossils beyond the oligocène, DE STEFANO refers to the presence of others, of Lizards especially (p. 387), which according to him prove yet better than the Snakes «la non eocenilà del deposito delle fosforiti del Quercy». His argument is that certain groups, as for instance Agamidae, Chamaeleontidae, Iguanidae have not been found up to now in the Eocene of Europe, which however is not yet a proof of their absence in Eocene strata,and consequently of the impossibility of their discovery. It even appears most pro ba ble that the organic world did not lay stress upon the observance of limits of geological ages, but inasmuch as higher specialized groups were in question, they often undoubtedly extended back towards older strata, in correspondence with the time necessary to their specialization. Therefore, according to my opinion this proof falls away, in principle at least. Another reason why the Eocene period ought to be kept out of consideration is that, as DE STEFANO expresses it, some types show «uno stadio di transizione» which seems to me to represent a principally yet weaker argument than the first «proof» above mentioned, for there is no cause why a «stadio di transizione» should be admitted only just in the Miocene and not. y<>t in the upper Eocene. Among Tailless Batrachians, Oxyglossus offers in an example as to how far back some re cent genera extend, remains of it being already to be found in the up per Eocene of India, which fact plainly shows as proved by palaeontological remains that the order Anura for instance, already constituted in the Jurassic a group specialized in the sense of today (compare: FEJÉRVÀRY, op. cit.). Difficulties likely to arise may also easily be dissolved by the fact of the fauna of Quercy belonging to three geological periods, the more developed types representing the later, the ancient ones the older strata. Thus even if it were possible to prove that,, according to DE STEFANO, certain Lizards truly only appear in the Miocene, this would yet be no proof to the lack of Eocene strata in the Quercy group (see next footnote). 1 From what has been developed in the preceding footnote it were in any case very difficult to determine exactly which individuals of the Quercy phosphorites may be considered to belong to the upper Eocene, and which to the Oligocène or under Miocene ; it is precisely the fact of the Quercy fauna embracing three periods which demonstrates the error of DE STEFANO'S arguments, for the forms which, according to the course of developement, prove younger, may be taken, as belonging to the more recent, the ancient ones to the older fauna.