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IV. A Contribution to our Knowledge of the Varieties of the Wall-Lizard (Lacerta 

 muralis) in Western Europe and North Africa. By G. A. Boulenger, F.R.S., 

 V.P.Z.S. 



Beceived November 22, 1904 ; read February 21, 1905. 



[Plates XXII.-XXIX. and Text-figures 1-6.] 



J.HIRTY years have now elapsed since special attention began to be paid to a 

 systematic study of the variations of the Wall-Lizard of the Mediterranean basin, our 

 knowledge of which has been so greatly advanced by the publications of Bedriaga, 

 Eimer, Braun, Werner, and others. It is Bedriaga who, by a valuable series of papers, 

 issued between 1874 and 18S3, has most contributed to this advance, from the 

 systematic point of view, Eimer's researches being more of a theoretical kind, and almost 

 entirely confined to Italy and Malta. And to Bedriaga also we are indebted for a 

 complete summary of the state of the question in 1886, at which date appeared his 

 great monograph of the genus Lacerta, published by the Senckenberg Society. Since 

 that time, however, a much larger material has been examined, and this has resulted in 

 new views on the definition of the races and on their mutual relationships. I have 

 always been keenly interested in the question, and have missed no opportunity of adding 

 to the collection in the British Museum, which is now a very imposing one, both from 

 the point of view of the number of specimens and of the variety of localities. 



Of late a tendency has sprung up to greatly multiply the species and thus destroy the 

 old conception of Lacerta muralis. I doubt whether such attempts will conduce to a 

 better understanding of the subject, and I have often been struck by the want of 

 discrimination in the selection of characters on which many of these supposed species 

 are founded. Characters of form and coloration are given as distinctive which on 

 examination of even moderately large series of specimens prove to be worthless, whilst 

 others of greater importance have been overlooked or neglected l . The object of this 

 paper is to supply detailed descriptions of the specimens in the British Museum, and by 

 drawing special attention to the individual variations, which are so frequently passed 

 over in systematic definitions, to furnish a sounder basis for future work. I have 

 endeavoured at the same time to review the work of my predecessors, so far as I 



1 Eimer, fur instance, attempted to classify the variations according to the pattern of coloration and the 

 shape of the head, practically neglecting everything else. His work, therefore, although extremely 

 interesting and containing much that is true as regards the derivation of markings, cannot be said to have 

 advanced our knowledge from the systematic and zoogeographical points of view. 



vol. xvn. — part iv. No. 1. — October, 1905. 3 a 



