154 MR. A. SANDERS ON LIOLEPIS BELLI. [Feb. 6, 



sexes. In G. vaillantii the moustache of the male is black and never 

 red, according to Malherbe (op. cit.) ; and in the female the crimson 

 does not extend beyond the occiput, whereas in the present species 

 it pervades the whole of the crown. 



9. Notes on the Myology of Liolepis belli. 

 By Alfred Sanders, F.Z.S. 



[Eeceived December 18, 1871] 



A specimen of Liolepis belli having come into my possession, I 

 think that an account of its myology may perhaps prove interest- 

 ing. A detailed description of the muscles of at least one species 

 of every family of the vertebrate subkingdom is, in my opinion a 

 great desideratum ; and a series of monographs on this subject could 

 not fail to throw light on many questions now in dispute. In the 

 photographs attached to this paper, I have as far as possible given 

 the origins and insertions of the muscles, together with the adjacent 

 points of bone, so as to give a_^ clear idea of the mutual relations of 

 the various parts. With regard to the nomenclature, it must be 

 regarded as merely a tentative expression of opinion, liable to be 

 changed at any time on the demonstration of error. 



Platysma myoides (fig. 1 ) is the most superficial muscle on the 

 ventral aspect of the throat ; it consists of a single, extremely thin 

 layer of muscular fibres; posteriorly it is lost in a thick stratum of 

 dark-coloured fat, which abounds about the anterior part of the 

 thorax; laterally it covers the mandible, and muscles attached thereto, 

 and passes into the superficial fascia of the back of the neck ; ante- 

 riorly it decussates with the fibres of the mylo-hyoid, passing through 

 them, and being inserted into the inner edge of the mandible in 

 front of the ectopterygoid ; more anteriorly the fibres pass trans- 

 versely between the two rami. This corresponds to the muscle called 

 hyo-mandibular in Gecko* in every respect except that it has no 

 connexion with the hyoid bone ; I may here remark that this name 

 was given by mistake in the latter instance, it having slipped my 

 memory that the same had been applied to a bone in fishes. 



Mylo-hyoid (fig. 1) arises from rather more than two thirds of the 

 anterior border of the proximal end of the posterior cornu of the os 

 hyoides (thyro-hyal, Owen) and from the body of the same (basihyal); 

 its fibres, proceeding straight forwards, are inserted into the inner 

 side of the dentary piece of the mandible, commencing immediately 

 in front of the insertion of the ectopterygoid ; anteriorly, as above 

 mentioned, they decussate with those of the platysma myoides ; the 

 insertion occupies not quite half the length of the ramus ; internally 

 the posterior part of the muscle is united to its fellow of the oppo- 

 site side by a raphe. 



Genio-hyoglossus (figs. 1 & 2) is situated dorsad of the last, and 

 * P. Z. S. 1870, pfc. ii. 



