THE COMMON LIZARD, LACERTA VIVIPARA 49 



lizards there are no glands in the skin, unless the 

 femoral and pre-anal pores which occur in this and 

 many other species are to be regarded as glands. 

 These pores are found on the under-surface of the 

 thighs, particularly in the males, and also in front of 

 the anal opening. Those on the thigh of the common 

 lizard number from nine to twelve. "Each of these 

 organs perforates a scale and leads into a tubular 

 invagination, which is lined with epidermal cells, the 

 proliferation of which produces a horny yellowish 

 debris, and this fills the tube and appears above the 

 surface in the shape of a little cone." ^ The function 

 of this excretion is not definitely ascertained, but 

 possibly it is concerned in gratifying some sense- 

 perception. Professor Cope remarks upon this : " The 

 use of this substance is uncertain, but it is probably 

 an important aid to the animal in maintaining its 

 hold on smooth surfaces. Lizards which move on 

 the ground rest nluch on the thighs, which are not 

 elevated above the ground in many types, but serve as 

 the principal point of contact from which they make 

 their leaps. The same is true of some genera which 

 leap among trees from branches and trunks. A 

 similar secretion issues from the pre-anal scales in 

 some Iguanidse {Liolcemus, etc.), and in an African 

 Lacertid a rudimental structure of this character is 

 found on many of the abdominal scales (Foroidogaster). 

 An approximation to this structure I have seen on 



^ Gadow, Amphibia and Reptiles, p. 553. 

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