THE INSECT WORLD. 



175 



Fui. 150. 



to destroy the also imported "cottony cushion-scale," Icerya 

 purchasi. The relation of these species has been already dis- 

 cussed when speaking of the scale, 

 and will be again referred to in Part 

 III. of this work. 



There are few rules without excep- 

 tions, and so we find sinners among 

 the lady-birds also, — all belonging to 

 the genus Epilachne. The species 

 are large, hemispherical, and yellow, 

 with black spots. The larvae are 

 also yellow, elongate oval, with long 

 branched spines. E. borealis is the 

 Northern and Eastern species at- 

 tacking cucumber, melon, and sim- 

 ilar vines, while E. corrupta is found 

 in the West and Southwest, injuring 

 beans. A curious feature in E. borealis 

 is the manner in which the adult 

 marks out a circle at the edge of a 

 leaf and feeds within it until all usable 

 tissue is exhausted, before proceeding 

 to another place to repeat the opera- 

 tion. 



As these injurious species feed 

 openly in all stages, they can be 

 reached without trouble by any of the 

 arsenites. 



The family Erotylidce contains some 

 very prettily marked species of quite 

 diverse forms, most of which feed in 

 or on fungi, or may be found under 

 loose bark, and are, therefore, innox- 

 ious. In the genus La/ignria, how- 

 ever, we find an exception, since their 

 larvae live in the stems of clover and 

 other plants. They are very slender, 

 almost cylindrical, from one-fourth to 

 one-half an inch in length, and have the wing-covers blue or 



Epilachne cotyupla. — A, adult ; 

 B, pupa; C, larva; D, injury on 

 bean. 



