538 LACERTAE CHAP. 



Some Anguis, at least, are viviparous. The distribution of the 

 seven genera, with some forty species, is very scattered. The 

 majority, chiefly Gerrhonotus, inhabit Central America, a few 

 occur farther north and south two, Anguis fragilis and Pseudopus 

 pallasi, in Europe, and one in the Himalayas and in Burmah. 



Gerrhonotus has a pair of deep longitudinal folds, each of 

 which extends from the region of the neck along the side of the 

 body towards the tail. The four limbs are well developed and 

 pentadactyle. The teeth are conical. Many species, mostly in 

 Central America. G. coeruleus has the widest range, extending 

 from Costa Kica to Vancouver. It is also one of the largest 

 species, reaching a length of more than one foot. The tail is 

 nearly twice as long as the rest of the body. General colour 

 above brown with blackish bars and spots, especially on the 

 more yellowish flanks ; under parts whitish with a greenish 

 tinge, often with brown spots arranged in longitudinal rows. 



Opliisaurus s. Pseudopus is closely allied to the previous 

 genus, being possessed of the same kind of deep lateral folds ; the 

 limbs are, however, reduced to a pair of tiny spikes, half concealed 

 at the sides of the anal cleft. The teeth are conical, and in the 

 adult, have somewhat flattened crowns. The body and tail are 

 very long and snake-like, but the head is that of a typical Lizard. 



0. apus s. Pseudopus pallasi, the Glass-Snake of the Balkan 

 Peninsula, South Kussia, Asia Minor, and Morocco, grows to 

 more than one yard in length, of which about two-thirds belong 

 to the tail. The general colour is brown above, paler below. 

 Young specimens are olive-grey with dark brown cross-bands on 

 the back. 0. gracilis inhabits the Eastern Himalayas and 

 Burmah, the others live in North America. 



The " Glass-Snake " inhabits bushy localities, where it can 

 hide under the fallen leaves and in the sand ; it cannot climb, 

 and avoids the water. Its movements resemble those of a 

 snake, but are far less graceful, owing to the stiff armour in 

 which the whole body is encased. The food consists chiefly of 

 snails, the shells of which are crushed, and of mice, but 

 nothing comes amiss which can be mastered, namely insects, 

 worms, small lizards, young birds, and vipers. The prey, when 

 caught, is rapidly twisted round and round, or shaken until it is 

 giddy or stunned, whereupon the Glass-Snake proceeds to chew it 

 with its powerful jaws, and then to swallow it in pieces. 



