189.-,.] Zoology. 151 



did not " admit," as alleged by Boulenger that these Lacertilia " agree 

 with the Ophidia," as they do not. Dr. Boulenger asks « what," under 

 these circumstances, " remains of Prof. Cope's new definition of the 

 suborders of the Squamata? " From what lias preceded it is evident, 

 first, that they are not " new " except as to theexoccipital ; and second, 

 that they remain intact, so far as any evidence to the contrary has 

 been produced by Dr. Boulenger, except as to the articulation of the 

 quadrate with the exoccipital in two genera of Agamida\ And it is 

 not necessary to observe that very few groups so closely allied as the 

 Lacertilia and Ophidia can be defined without exceptions. 



If we now look at the definitions given by Dr. Boulenger in his vol- 

 umes of catalogues of lizards and of snakes in the British Museum, th. 

 necessity of something better becomes at once apparent. The Lacer- 

 tilia are thus defined : " Quadrate bone articulated to the skull : parts 

 of the ali- and orbitosphenoid regions fibrocartilaginous ; rami of the 

 mandible united by suture ; temporal region without or with only one 

 horizontal bar. Anal cleft transverse. Copulatory organs paired. 

 Gunther." 



The definition of the Ophidia (dated 1893) is as follows : " Quadrate 

 bone articulated to the skull ; brain capsule entirely osseous ; rami of 

 the mandible articulated by ligament. Anal cleft transverse. Copu- 

 latory organs present paired. Gunther." 



In these definitions the first and last two are identical in both. The 

 presence or absence of a horizontal bar is not definitive, and indeed no 

 reference to it is found in the definition of the Ophidia. The only 

 definitions left are those derived from the mode of union of the sym- 

 physis mandibuli, and the ossification of the brain case. The former of 

 these characters is not found in several families of Lacertilia, and the 

 latter is the one which Dr.Boulenger has repudiated in the note which 

 gave origin to this reply. I think my attempts at definition do, in 

 point of precision and application, compare very favorably with those 

 which seem to have satisfied Dr. Boulenger in the work cited. In 

 another publication he gives the characters usually employed, which 

 are much better. 



In a recent synopsis of the species of CasciliidaV Dr. Boulenger 

 make3 some observations on the relations of this family to the rest of 

 the Urodela. He remarks : " If the absence of the limbs and reduc- 

 tion of the tail were the only characteristic of the group, I should, of 

 course not hesitate to unite the Cacilians with the Urodeles ; but, to 

 say nothing of the scales, the Csecilian skull presents features which 

 are not shared by any of the tailed Batrachians, and the order can be 



» Proceeds. Zool. Soc, London, 1895, p. 402. 



