358 INSECTS INJURIOUS TO VEGETATION. 



with the body extended from the branch, so that they might 

 be mistaken for a twig of the tree ; and in this position they 

 will often remain for hours together. When about to trans- 

 form, most of these insects descend from the plants on which 

 they live, and either bury themselves in the ground, or conceal 

 themselves on the surface under a slight covering of leaves 

 fastened together with silken threads. Some make more 

 regular cocoons, which, however, are very thin, and generally 

 more or less covered on the outside with leaves. The cocoons 

 of the European, tailed Geometer ( Ourapteryx samhucaria)^ 

 which lives on the elder, and of our chain-dotted Geometer 

 [Geometra ca^ewma), which is found on the wood-wax, are 

 made with regular meshes, like net-work, through which the 

 insects may be seen. A very few of the span-worms fasten 

 themselves to the stems of plants, and are changed to chrysa- 

 lids, which hang suspended, without the protection of any 

 outer covering. 



In their perfected state these insects are mostly slender- 

 bodied moths, with tapering antennae, which are often feathered 

 in the males. Their feelers are short and slender; the tongue 

 is short and weak ; the thorax is not crested ; the wings are 

 large, thin, and delicate, sometimes angular, and often marked 

 with one or two dark-colored oblique bands. They generally 

 rest with the wings slightly inclined and almost horizontal; 

 some with them extended, and others with the hind wings 

 covered by the upper pair. A very few carry their wings like 

 the Skippers. Some of the females are without wings, and 

 are distinguished also by the oval and robust form of their 

 bodies. These moths are most active in the night; but some 

 of them may be seen flying in thickets during the day-time. 

 They are very short-lived, and die soon after their eggs are 

 laid. 



Those kinds, whereof the females are wingless, or have only 

 very short, scale-like wings, and naked antennse, while the 

 males have large, entire wings, and feathered or downy an- 

 tennae, seem to form a distinct group, which may be named 

 Hybernians (HyBERNiAD.E), from the principal genus included 

 therein. The caterpillars have only ten legs, six before and 



