IIEMIPTERA. 215 



among plants. They live, both in the perfect and young state, 

 upon plant-lice, and hence their services are very considerable. 

 Their young are small flattened grubs of a bluish or blue-black 

 color, spotted usually with red or yellow, and furnished with 

 six legs near the fore part of the body. They are hatched 

 from little yellow eggs, laid in clusters among the plant-lice, 

 so that they find themselves at once within reach of their prey, 

 which, from their superior strength, they are enabled to seize 

 and slaughter in great numbers. In July, 1848, a friend sent 

 to me a whole brood of lady-bird grubs, which, being found 

 upon potato-vines, were thought by some of his neighbors to 

 be the cause of the rot. In a few weeks, the grubs were trans- 

 formed to beetles, about as big as half a pea, and having nine 

 black dots on their dull orange-colored wing-shells. Hence 

 they derive their name of Coccinella novemnotata, the nine- 

 dotted Coccinella. It need hardly be added that these little 

 insects were wholly innocent of all offence to the plants, upon 

 which, when infested with the common potato plant-lice, they 

 may always be found. It is amusing, however, that both of 

 these kinds of insects should have been charged with the same 

 fault, one having no more to do with producing the disease 

 than the other. 



There are some lady-birds, of a very small size, and blackish 

 color, sparingly clothed with short hairs, and sometimes with 

 a yellow spot at the end of the wing-covers, whose young are 

 clothed with short tufts or flakes of the most delicate white 

 down. These insects belong to the genus Scymnus, which 

 means a lion's whelp, and they well merit such a name, for 

 their young, in proportion to their size, are as sanguinary and 

 ferocious as the most savage beasts of prey. I have often 

 seen one of these little tufted animals preying upon plant-lice, 

 catching and devouring, with the greatest ease, lice nearly as 

 large as its own body, one after another, in rapid succession, 

 without apparently satiating its hunger or diminishing its 

 activity. 



The second kind of plant-lice destroyers are the young of 

 the golden-eyed lace-winged fly, Chrijsopa perla. This fly is 

 of a pale green color, and has four wings resembling delicate 



