der ' Muralis-i^/'a^f.' " 41 



platycephalous than tliat of the typical L. murah's, which 

 falls in the platjcej^halous group of Mehelj. Besides, tlie 

 works of Eimer and of Bedriaga sliow, in several instances, 

 th.at these authors have been unable to correctly appreciate 

 the character to which, in my opinion, they have attached too 

 great importance *. 



Yet, when we compare extreme forms, such as var. cam- 

 pestris or Jiumana, on the one hand, and var. Bedn'agce'f or 

 snrdoa on the other, the difference in the two types of heads 

 stands out very strikingly. We are not much the wiser when 

 the skulls have been prepared, as the characters pointed out 

 by Prof V. Mdhely are, for the most part, correlative of the 

 degree of elongation or depression of the head, which can be 

 appreciated without injuring the specimens. It must be 

 borne in mind that skulls of lizards cannot be extracted as we 

 do in the case of mammals. Preparing the skull means the 

 partial destruction of the specimen, and in a discussion of 

 this kind, dealing mainly with individual variations, annectant 

 examples cannot always be sacriticed. Prof. v. Meliely has 

 given us figures of two extreme types of skulls, but I could 

 easily lay out a series that would to such an extent bridge over 

 the differences as to show of how little practical value they 

 are for the definition of species. A discovery of Prof. v. 

 Mdhely's is the incomplete ossification of the supraocular 

 region in the most pronounced platycephalous wall-lizards. 

 But even here he is obliged to make this restriction — that in 

 some, in the var- Bedriagce, for instance, the fontanel le in the 

 supraocular bony plates is "nicht immer vorhanden " in adult 

 males. The character is therefore not of so great importance 

 after all. 



What surprises me most is to find that Prof, v. ]\lehelj 

 is not at all aware of the individual variations which occur in 

 the skulls of the forms which he classifies as "reinplaty- 

 cephal" and "rein pyramidocephal." Thus he attaches a 



* For instance, in the yars. mf/riventris, serpa, aud quadrilinenta, some 

 specimens ha\e been referred by Bedriajza to the pyramiducephalous 

 group (i. muralis neapolitana, Bedr.) and others of the same race to the 

 platycephalous {L. muraUs fusca, Bedr.). Eimer regards the Maltese 

 lizard as platycephalous and its Filfola derivative as pyramidocephalous, 

 a distinction which is not borne out by the material at my disposal. 

 Werner has also fallen into the same pit, in describing examples of the 

 same form {L. muralis littoralis, Werner) under the two groups (vars. 

 lissana and Jiu ma na). I myself do not blush at confessing similar errors, 

 due, perhaps, more to the nature of things thau to any want of " Scharf- 

 blick " on my part. 



t Prof. v. Mehely calls this lizard L. reticulata, Bedr. But this name 

 is otherwise employed in the genus Lacerta i^L. muralis reticulata, 

 Scbreiber, Eimer). 



