With some species, students were unable to discover geographi- 

 cal races by means of old classical methods based on the observa- 

 tion and detailed description of a few specimens. A new hope 

 arose when mathematical methods were applied to the study of large 

 samples of specimens. But often even the most detailed statistical 

 analysis did not substantiate geographical races. So it was clear 

 that there were species with intense population and individual 

 variability; but this variability did not always permit the defi- 

 nition of geographical races. This was established, for instance, 

 in the case of the Eurasiatic viviparous lizard ( Lacerta vivipara 

 JACQ), by TERENTJEV (1948) and WERMUTH (1955). WERMUTH established 

 that geographical variation of some morphological features was 

 independent of other characters. The theory of geographical races 

 includes an implicit correlation between the trends in the geo- 

 graphical variation of the species characters. STUGREN and VANCEA 

 (1961) established similar evidence for the viviparous lizard from 

 Rumania, in a study of populations from the Eastern and Southeastern 

 Carpathian Chains and from the Western Mountains (Apuseni Mountains 

 in Rumanian). Even in this last massif where the populations of 

 L. vivipara have been entirely isolated from the main area of the 

 species since the warmer postglacial period, no geographical race 

 has developed. The authors noticed that morphological differences 

 between males and females in a population are (statistically con- 

 sidered) more significant than those between individuals belonging 

 to the same sex but living in different areas. With regard to the 

 correlation between the variation of morphological characters, 

 STUGREN and VANCEA observed three groups of traits, using the Chi 

 square - test : 



1. Characters which vary independently (density of squamae 

 temporalia versus constellation of squamae praef rontal ia , 

 and versus the index of density of squamae dorsalia 

 (Schuppendichte- Index) . 



2. Characters which apparently vary independently from 

 each other, but the hypothesis of an independent distribu- 

 tion has a low probability (constellation of squamae 

 praef rontalia versus the index of density of squamae 

 dorsalia) . 



3. Characters which are correlated (density of. squamae tem- 

 poralia versus the conformation of the scutellum masseter icum — ' 



1). As defined by SCHREIBER in the scond edition of his work 



" Herpetologia europaea" (1912), the scutellum massetericum is 

 a larger central scale in the temporal region of the head of 

 some lizards. 



2. 



