STUDY OF REPTILES 115 



mostly with scales, a vertical (not round) pupil, and, moreover, 

 when attacked usually coils itself into a spiral disc with the head 

 standing out in the middle ready to strike." 1 It is quite harmless, 

 and crushes in its coils the mice and lizards which it catches, being 

 unable to paralyse them with a poisonous bite as the adder does. 

 It usually hunts in the evening. 



The smooth snake is viviparous, and about six young ones are 

 born at a time. 



The Greek tortoise Testudo grceca and the closely allied 

 Moorish tortoise T. ibera are often brought to this country, and 

 in the warmer parts they seem to thrive in gardens. They are 

 usually quite strict vegetarians, enjoying succulent food, and they 

 certainly do not eat " black beetles," though they are often sold 

 and bought for this purpose. They are entirely diurnal and enjoy 

 the sun ; they hibernate in winter. The pairing is in spring or 

 summer ; two to four hard-shelled eggs, like those of pigeons, are 

 buried in the ground. Tortoises are very tenacious of life, and 

 may live for more than half a century. 



The tortoise may be taken as an illustration of effective armour. 

 It can retract head and tail and limbs within the shelter of its 

 arched shell, which is exceedingly strong. The Greek eagle 

 breaks up the Greek tortoise by letting it fall from a great height 

 (a habit which is said to have been fatal to the poet ^Eschylus), 

 and it is interesting to compare this with what has been observed 

 in regard to rooks, that they get into freshwater mussels by letting 

 them fall from a height, and with the thrush's well-known habit 

 of breaking snails' shells against stones. 



A cleaned shell should be sawn across vertically to show the 

 strong arch, and the inside of the upper half should be studied 

 to show this at least, that the dorsal vertebrae and the ribs have 

 become part and parcel of the shell, and that the contours of the 

 epidermic horny scales (tortoise-shell) do not in the least correspond 

 to the contours of the bony plates. 



Suggested Study. Different types of animals may be utilised 

 educationally in different ways, thus the life-history of the frog 

 is readily studied while that of a snake is not ; birds have, so to 



1 Hans Gadow, see references at the end of the chapter, p. 119. 



