562 INSECTA— ORDERS COLEOPTERA AND ORTHOPTERA. 



covered many miles from the sea-coast in some potato fields at Miilheim-on- 

 Khine, nearly opposite Cologne. The fields were at once ploughed up, drenched 

 with petroleum and burned over; and the pest was fortunately stamped out 

 The scare has now subsided, but it is all the more necessary for us to be pre- 

 pared to take equally prompt and energetic measures if the Uolorado beede 

 should happen to make its appearance among us, as is always possible 

 enough, perhaps at some out-of-the-way place where it is least expected. 



Among the largest and most conspicuous of the foreign species of this 

 group are the species of the genus Sagra (Fabr.), which are found in the East 



Indies and Africa. Tliey are long, smooth 

 Turnip-Beetles, beetles, of a brilliant green colour, sometimes 

 varied with coppery red, or purple, and the 

 hind femora are of very large size, being constructed for 

 leaping. These beetles are an inch long, but the destruc- 

 tive turnip-beetles, belonging to the genus Phyllotreta (Latr.j, 

 have also thickened hind femora, and skip about like fleas. 

 They are oval, and less than a q\iarter of an inch in length. 

 The elytra are bronzy black, and marked with a yellow stripe. 

 They are often called "Turnip Flies," but turnip flea- 

 beetles would be a more appropriate term. Our figure 

 of Phyllotreta nemorum (Linn.) is somewhat above natural size. 



The last of the great group of beetles are the Pseudotrimera, which are 



small species, distinguished by having only three visible joints to the tarsi. 



The best known of these are the lady-birds (CocciiieUidai). 



Lady-Birds. of which there are a considerable number 

 in England. They are small round beetles, 

 and the elytra are mostly red with black spots, or black 

 with red or yellow spots. The head and thorax are black 

 with white markings. They are very useful insects, for 

 they are carnivorous, and destroy large numbers of Aphides, 

 or plant-lice. 



We have figured the typical form of one of the commonest 

 species, Coccinella bipnnctata (Linn.), slightly magnified. It H^^fc'^tidh 

 is very variable, and the elytra are sometimes almost black, biimrtctata). 



instead of being red, with a black spot on each, as in our figure. 



Other families of this group are the Triehopterygidtf, the smallest of all 

 beetles, and if we except some of the egg-parasites among the Eymenoptera, 

 almost the smallest insects known. They are little black beetles, with 

 long, slender, clubbed antennae, and are found among decaying vegetable 

 refuse. 



Other species belonging to the Pseudotrimera are found in fungi, and 

 others, again, inhabit ants' nests, where, it has been suggested, they may be 

 preserved as pets. 



Oedee Oethopteea (Ceickets, Locusts, etc.). 



The Order Orthoptera, or straight- winged insects, includes the earwigs, cock- 

 roaches, crickets, grasshoppers, locusts, etc. These are all insects with 

 strong jaws, instead of a proboscis, and differ from the other mandibulate 

 orders by the fore-wings (which are called in Orthoptera not elytra, but 

 tegmina) being generally of a different consistency to the others throughout, 



