COLEOPTERA 



i53 



are known as " niggers " by hop-growers, and are greatly prized by them; 

 for they are very destructive to the hop-louse. On the Pacific Coast lady- 

 bugs are well-known as the most beneficial of all insects to the fruit-growers. 

 In addition to the native species found there, several species have been 

 introduced as a means of combating scale-insects. One of these, 

 Rodolia cardinalis, has proved of very great value in subduing the 

 cottony-cushion scale (Icerya purchasi). This lady-bug was introduced 

 from Australia. 



A very common one is the two-spotted lady-bug, Adalia bipunctdta. 

 This species is reddish-yellow above, with the middle of the prothorax 

 black, and with a black spot on each wing-cover. It frequently passes 

 the winter in our dwellings, and is found on the walls and windows in 

 early spring. Under such circumstances it is often mistaken for the 

 carpet-beetle, and, unfortunately, destroyed. (See Plate I,Figure3). 



The nine-spotted lady-bug, Coccinella novemnotdta, has yellowish 

 wing-covers, with four black spots on each, in addition to a 

 common spot just back of the scutellum (Fig. 263). fig. 263. 



There are two " black sheep " in this family of lady-bugs, namely, 

 the squash lady-bug, Epildchna boredlis and the bean lady-bug, Epilachna 

 corrupta. The adults and larvae of both of these species are herbivorous 

 and injurious, especially those of the latter. The bean lady-bug from its 

 former home in the south-western states, suddenly appeared in Alabama 

 in 1 919 and has now spread over most of the eastern United States and 

 into Canada. It is pale yellowish to orange-brown and from \ to § of an 

 inch in length. Each wing-cover has eight black spots arranged in three 

 transverse rows. The larva? and adults feed on bean plants and are very 

 destructive. 



Fig. 264. 



The squash lady-bug lives on various cucurbitacecus plants but it 

 prefers the squash and often becomes destructive (Fig. 264). 



