LOOPING CATERPILLARS. 231 



caterpillars can be at once recognised as belonging 

 to the Geometrae, and every entomologist knows that 

 if he should find a looping caterpillar, and rear it, the 

 result will certainly be a Geometra Moth of some 

 kind. 



In the perfect state it is not so easy to distin- 

 guish the Geometrae, though there is a certain and 

 almost indescribable aspect about them that a prac- 

 tised entomologist rarely fails to detect, even though 

 the species be new to him. We will now proceed to 

 examine some of the most characteristic of these 

 Moths in detail. 



THE first family of the Geometrae is called Ur- 

 apterydae, or Wing-tail Moths, because in them the 

 hinder wings are drawn out into long projections, 

 popularly called ' tails.' In England we have but one 

 insect belonging to this family, the beautiful, though 

 pale-coloured, S WALLOW-TAILED MOTH (Urapteryx 

 sambucata). The generic name is spelt in various 

 ways, some writers wishing exactly to represent the 

 Greek letters of which it is composed, and others 

 following the conventional form which is generally in 

 use. If the precisians are to be followed, the word 

 ought to be spelled Ourapteryx. 



There is no difficulty in recognising this Moth, 

 the colour and shape being so decided. Both pairs of 

 wings are delicate yellow, and the upper pair are 

 crossed by two narrow brown stripes, which run from 

 the upper to the lower margin. These stripes are 

 very clear and well-defined, but besides there are a 

 vast number of very tiny streaks of a similar colour, 



