COLEOPTERA. 131 



trees are sometimes so crowded with these splendid insects 

 that the branches bend beneath their glittering burden. 

 Even some of our native species, such as the Rose curculio 

 when seen under a microscope, are found to be most bril- 

 liantly decorated. 



A second section of Coleopterous Trimerans com- 

 prehends 



The Wood Eaters or Xylophagi,* a race of insects 

 specially appointed to devour timber. They mostly 

 live upon wood, in which their larvae excavate gal- 

 leries in all directions, so that when they become 

 numerous, whole forests of pine and fir are destroyed 

 by their ravages ; some cause immense damage 

 amongst olive-trees, whilst others, the feeblest of 

 the race, content themselves with devouring various 

 kinds of fungi. 



As an example of these timber borers, we give a 

 figure of 



The Long-horned Beetle (Prionus), one of the largest 

 of the tribe, conspicuous alike from the beauty of its 

 colours and the strength of its jaws. (Fig. 87.) 



In the last section of the Coleoptera, the 

 Trimerans, the number of tarsal joints in all the 



six legs is reduced to three ; of these the best known 



examples are 



The Lady-birds (Coccinella), universal favourites, and 

 as useful as they are pretty. These insects are readily 

 recognised by their semi-globular shape, and by the pecu- 

 liar pattern of their colouring, generally black spots upon 

 a red or yellow ground, or red and yellow spots upon a 

 black ground. They feed exclusively upon the plant-lice 

 or Aphides that infest the choicest flowers of our green- 

 houses, and are still more hurtful in the hop-plantation 

 and the garden. To the destruction of these insect pests 

 the whole energies of the Lady-bird are devoted. Its eggs 

 are laid in little patches on the leaves of plants, resembling 

 groups of nine-pins set upright; when these are hatched 

 they give birth to a larva furnished with a small head and 

 a thick but tapering body, which creeps actively about the 



* uAov, xylon, wood; Qayeiv, phagein, to eat. 



