USEFUL INSECTS 



beetles, the body being soft and flexible, and covered with a yellowish-grey 

 down. The female has neither wings nor elytra, and has the power of emitting 

 a strong phosphorescent light from the underside of the last three segments 

 of the body. The male has well-developed wings and elytra, and emits only 

 two tiny spots of light. The larva greatly resembles the perfect female, and 

 does great service for the agriculturalist in attacking and devouring snails. 

 During April or May the larva pupates, and the perfect insect appears in 

 a fortnight or a little more. 



The Seven-spot Lady-bird (Coccinella septempunctata) is a great friend of 

 the horticulturalist and agriculturalist, waging incessant war on the aphides, 

 preserving for the use of man much which would otherwise be lost. The 

 perfect insect has a black head and thorax, and red elytra usually bearing 

 seven black spots, three on each elytron, and one near the base of the suture. 

 The larva? are slaty and yellow, with black spots and hairy tubercles down 

 the back, mixed with orange spots. They are popularly known as " niggers," 

 and are exceedingly voracious, soon clearing a plant of aphides, literally by 

 the thousand. So serviceable are they that they should never be disturbed. 

 When full-fed they attach themselves to a twig or leaf by the end of the 

 tail, and hang downwards, and the pupa? remain in the larval skin till 

 changing into the perfect form. The disagreeable odour attached to the 

 Lady-birds is connected with a yellowish liquid secreted from the joints of 

 the limbs. 



The Two-spot Ladybird {Coccinella bipunctata) is another common species. 

 The wing-cases are usually scarlet, bearing a black spot on each, but the 

 colouring varies considerably from red and black to entirely black. 



The Sun Beetles (Ptcrostichus) number more than twenty species. They 

 are very varied in colour, generally green, bronze, or bluish-black, the elytra 

 being marked with regular stria?. They are very voracious, feeding on a 

 large number of insects, darting swiftly over the ground when in quest 

 of food. 



The Lacewing Fly (Chrysopa vulgaris) is one of man's best friends in 



the garden and orchard. The Hy is a delicate and beautiful insect, not 



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