92 INVERTEBRATE ANIMALS. 



The females of certain species are without wings. 

 Geometrce, of which about 270 kinds inhabit Britain, - 

 are sometimes seen in the cold grey light of a winter 

 evening, but more characteristically they are the butter- 

 flies of the summer twilight. Whilst the NoctucB and 

 other more robust moths, passing swiftly by, seem 

 always in haste, these slender and delicately- coloured 

 insects flutter leisurely along the hedge-side in the 

 gloaming, apparently in a condition of perfect enjoy- 

 ment. 



Upper Compartment. 



Specimens of preserved larvae, showing protective 

 mimicry. 



Section BOMBYCINA. /3o>/3u^, the Silk-worm. 



Group 206.— Genus SATUKNIA and allies. This group 

 includes amongst its constituents upwards of 40 silk- 

 producing moths, the larvse of which secrete the silk in 

 two large intestine-like vessels which unite at the 

 mouth in a common tube called the spinneret; through 

 this tube is ejected the secretion which, as soon as it 

 comes in contact with the air, hardens into a shining 

 fibre known as silk. 



Observe the configuration of the shaded pattern in 



Brahmcea and the talc-like spot in Attacus Atlas. 



Upper Compartment, 



The Ailanthus Silk-moth, ^^facus Cynthia, Cocoons, 

 Silk, &c. ; also Cocoons and Silk of the Tusser 

 and various other Silk-worms, presented by F. 

 Moore. 



Group 207. — Genus ARCTIA and allies. Observe examples 

 of the exotic genus Histia from Northern India and 



