6 The Butterflies and Moths of Teneriffe. 



markings of the new coat often vary from those of the 

 one cast off, and an experienced entomologist can tell 

 the age of the caterpillar by the colour and texture of 

 the skin in many varieties. When the creature has 

 passed through the larva and arrived at the pupa state, 

 it has at first a soft and tender skin, through which parts 

 of the future butterfly can be clearly seen ; this soon 

 hardens, however, and forms a case impervious to rain 

 or other atmospheric influences. 



Before taking the pupa form some caterpillars creep 

 into holes and crevices of walls and old buildings, others 

 bury themselves in the earth ; some envelop themselves 

 in a tissue of silk which they spin as a silkworm does, 

 and this case is called a cocoon. Other species draw a 

 leaf round their bodies, fastening it together with silk- 

 like threads, and so making a complete shelter for itself. 

 The Aurifera caterpillar is an example of this type, 

 being commonly found in Teneriffe on the potato plant, 

 from the leaf of which it constructs its house. Still 

 further varieties suspend themselves to a bough or leaf 

 head downwards. There are other varieties which 

 suspend themselves from the centre of their bodies 



