234 TEXT-BOOK OF ZOOLOGY 



— to mountains, woods, moors, and in general more elevated and moister 

 localities. The ground colour of this species is a more or less deep 

 brown with darkish stripes and lighter coloured dots extending along the 

 back and the sides of the body. It obtains its name vivipara from the 

 fact that the young leave the eggs before they are laid. 



The beautiful Green Lizard (L. viridis) is a native of the countries 

 of the Mediterranean, but is also found in the warmer parts of Germany 

 (e.g., in the valleys of the Danube and Khine). In Southern countries 

 it attains to a length of as much as 17 inches. 



The Wall Lizard (L. muralis), an equally pretty but much smaller 

 animal (length up to 9 iribhes), has the same range as the green lizard. 

 Sunny walls and cliffs are its favourite resorts. In the warm sun it 

 glides about with incomparable speed and nimbleness, and by the aid of 

 its sharply-clawed toes can even climb up vertical walls. Its colour is 

 very variable, but mostly brown or gray, like the ground which it 

 frequents. 



One of our most familiar species is the Blind- Worm or Slow- Worm 

 (Anguisfragilis), a harmless animal, devoid of limbs, and moving after 

 the manner of a snake. (Why is it not classed among the latter ?) The 

 body of this animal is covered with bony scales, which render its move- 

 ments stiff and awkward as well as slow. (Hence the name slow-worm ; 

 the designation blind- worm, however, is a misnomer, and is due to the 

 fact that in the dead animal the eyes are closed by the lids, which is not the 

 case in a snake.) Active insects being accordingly beyond its reach, its food 

 consists principally of earth-worms and slugs. As these animals mostly 

 emerge from their holes at night or after rain, the habits of the slow- 

 worm are also nocturnal, except in wet weather. Its colour resembles 

 that of the soil or of dry herbage. On a peaty soil it is nearly black (pro- 

 tective colouring). It brings forth living young (see viviparous lizard). 



Of the numerous lizards inhabiting warmer countries only a few will 

 be mentioned. (Why are lizards far more numerous in warm countries ?) 

 The Gecko (Tarentola mauritanica) is met with on the shores of the 

 Mediterranean on rocks, walls, and in human dwellings. Its length is 

 about 6 inches, and its colour, corresponding to its habitat, varies from 

 grey to brown. The most remarkable fact about this animal is that it is 

 capable, contrary to the laws of gravity, of running about on vertical walls, 

 and even the ceilings of rooms. The five toes, in fact, are widened out 

 into discs, and are furnished below with transverse membranous lamellae, 

 which are imbricated — i.e., cover each other like the slates of a roof. 

 When these lamellae are appressed to any object, a part of the air enclosed 

 between them is driven out. When the pressure ceases, the lamellae are 

 erected, spaces containing rarefied air being thus formed between them,. 



