Revietvs — G. A. Boulenger— Eocene Lizards. 375 



of most palfeontologists. Tlie idea that in JTafteria we had the 

 most generalized type of reptilian skeleton found among recent 

 reptiles, and the belief that Pal(eohatteria was a member of the same 

 group, for a long time misled most writers as to the inter- 

 relationships of the Reptilia. Cope, however, had already pointed 

 out that the temporal region of the skull si;pplied the surest basis 

 for forming an opinion as to reptilian affinities, and this idea was to 

 a great extent carried out by A. S. Woodward. Osborn & McGregor 

 made still more extensive use of these characters in drawing up 

 their well-known system of classification. Professor Williston 

 likewise employs the same characters, but has arrived at somewhat 

 different conclusions from the two last-mentioned writers. 



The main divisions he adopts are (1) Anapsida, (2) Synapsida, 

 (3) Parapsida, (4) Diapsida. The first includes the Cotylosauria and 

 the Chelonia, the former having no temporal opening in the skull and 

 being probably directly derived from the same stock as the Stego- 

 cephalia. The second includes the Theromorpha, Therapsida, Sauro- 

 pterygia, and Placodontia, in which there is a single temporal fossa 

 which he believes arose from a separation of the jugal and squamosal. 

 In the third, which includes the Ichthyopterygia, the Squamata, 

 Proganosauria, and Proterosauria, there is likewise only a single 

 temporal opening, which, however, is regarded as having been formed 

 independently of the openings found in other phyla, the streptostylic 

 type of skull found in the Squamata having arisen from the cutting 

 away by the lower edge of an originally broad squamosal bar such as 

 is found in the Permo-Carboniferous Arceoscelis. The fourth group, 

 the Diapsida, includes the remaining reptiles, in which there are two 

 temporal fossse (lateral and superior), of which the lower one is 

 regarded as the older, the upper having arisen as the result of a 

 secondary separation of an orbito-squamosal arch. The introduction 

 of the name Parapsida for a separate phylum including such, at 

 first sight, dissimilar types of reptiles as the Ichthyosauria and the 

 Squamata is the chief innovation in this paper, but the writer gives 

 good reasons for its introduction, as he does for his other conclusions. 



YIII. — Eocene Lizaeds in Pkance. By G. A. Boiilengek. 



IN a recent note published in the Comptes Pendus of the Academy 

 of Sciences, Paris (vol. 166, p. 889), Mr. Boulenger has shoAvn 

 that some of the genera of lizards (e.g. Placosaurus, Gervais, and 

 Fleatiodon, Pilhol), from the Upper Eocene Phosphorites of France, 

 belong to the family Helodermatidae, which at the present day is 

 represented only by the poisonous Gila Monster [Heloderma) of 

 Arizona and Mexico and by Lanthanotus of Borneo. The determination 

 of the relationships of these Phosphorite lizards was made possible 

 by the discovery of a skull showing the rudimentary condition of the 

 squamosal characteristic of the family. Mr. Boulenger is also able 

 to state definitely that the dermal scutes described by Filhol under 

 the name Necrodasypus, in the belief that they belonged to an 

 Armadillo, are in fact cranial scutes of these Helodermatid lizards. 



