566 LACERTAE 



If the tonerue and the dentition be taken as indications of 

 relationship, the Amphisbaenidae may perhaps be considered as 

 degraded descendants of Iguanidae, a family which contains 

 various limbless, burrowing, worm-shaped forms. But it is also 

 possible that the Amphisbaenidae are not a natural group. 

 This consideration applies with most force to the genera Amphis- 

 haena and AtiojJS, the various species of which occur in America 

 and in Africa. 



Ghirotes canaliculatus, the only species of the genus, is the 

 only Amphisbaenid which still possesses fore-limbs. These are 

 short, stout, placed close behind the head, and are provided with 

 four-clawed digits. This species occurs in Mexico and California, 

 is brownish or flesh-coloured, and reaches a length of about 8 inches. 



Amphishae7ia, with nearly thirty species, in Tropical America 

 and Africa. On account of the short rounded-off head and the 

 almost equally blunt tail these creatures are called by the natives 

 " cobras de dous cabezas," i.e. snakes with two heads, or they are 

 known as " maes das formigas," i.e. mothers of ants, because of 

 their predilection for taking up their quarters in the nests of 

 ants or termites. The scientific name refers of course to their 

 capal^ility of moving forwards and backwards (a/^^t?, at both ends, 

 and j3aiV(o, walk). 



A. faliginosa, one of the commonest species in South America 

 and in the West Indies, is chequered black and white. The skin 

 of the body has about two hundred rings, the tail about thirty. 

 Total length between one and two feet. A more or less distinct 

 fold extends along each side of the body from the neck to the 

 tail, at the level where the dorsal scales originally joined the 

 ventral scales. 



Blanus is the only genus of the Mediterranean province. 

 B. cinereus, of Portugal, Spain south of the Cantabrian range, 

 Morocco, and Algeria, reaches a length of 1 inches, but such large 

 specimens are rather rare. The general colour of the living 

 animal is pink with a brownish tinge and with minute grey 

 specks. The lateral lines or folds are well marked, and a stronger 

 transverse fold is placed behind the head. The l)ody shows 

 from one hundred and ten to one hundred and twenty-five 

 rings, the tail from twenty to twenty-two ; each body-ring con- 

 tains about thirty little squares or remnants of scales. There are 

 a few pre-anal pores. 



