26 



The following species have been captured on dates which indicate 

 that they hibernate as adults: 



MegUla maeulata DeG. — Several hundred examples taken March 31, 1900, at 

 Urbana, 111. It is a common species in that locality. 



Hippodamia glacialis Fab. — Taken at Maiden, Mass., November 4, 1897. 



Hippodamia parenthesis Sen/. — Taken at Maiden, Mass., November -i, 1897. Taken 

 at Urbana, 111., April 5, 1900. 



Coccinetta trifasciata Linn. — Taken at Maiden, Mass., April 13, 1898. 



Coccinella 9-notata Hhst.— Taken at Maiden, Mass., April 12, 1898. 



Coccinella sanguinea Linn. — Taken at Maiden, Mass., May 1, 1898, Taken at Urbana, 

 111., April 15, 1900. 



Adalia bipunctata Linn. — The most common species in eastern Massachusetts occurs 

 under loose bark of trees and in sheltered places during the winter. 



Harmonia picta Rami. — Taken at Maiden, Mass., May 1, 1898. 



Mysiapullata Say.— Taken at Maiden. Mass., May 2, 1898. 



Anatis 15-punetata Oliv. — Taken at Maiden, Mass.. January 12 and April 10, 1898. 



ChUocorus bivulnerus Muls. — Taken at Maiden, Mass., April 13, 1898. Taken at 

 Urbana, 111., April 26, 1900. 



PentiMa misella Lee — Taken at Lakeside, Ohio, October 27, 1900. Large colonies 

 were found under cloth bands, which had been tied around the trunks of plum 

 trees infested with San Jose scale. There were thousands of beetles in this orchard. 



Brachyacantha ursina Fab. — Taken at Maiden, Mass., May 5, 1898. 



Hyperaspis signata Oliv. — Taken at Maiden, Mass., May 1, 1898. 



Of the 14 species above listed, Megilla maeulata and A<l<<li<i Mpunc- 

 tata were the only ones which were found during the winter in colo- 

 nies. In most cases isolated beetles remain during the winter under 

 the loose bark of trees or under leaves or rubbish, and come forth on 

 the first warm days in spring to search for food. 



Early in the spring of 1898 they were first found feeding upon 

 plant-lice eggs. These ^ggs do not hatch until several days after the 

 beetles appear; hence this habit of the beetles serves to reduce the 

 number of lice considerably. 



April 13, 1898, many specimens of Adalia h /punctata were found 

 feeding on the eggs of an aphid, which was particularly abundant on 

 the white birch at Maiden. A few days later Anatis 15-punctata, 

 Coccinella sanguinea, C. 9-notata, and ChUocorus bivulnerus. as well as 

 Adalia bipunctata and its variety, humeralis, were found busily engaged 

 in feeding on the aphid eggs. Thousands of specimens of Adalia were 

 present, and large numbers of Anatis. the other species occurring in 

 moderate quantities. Three days later both Adalia and Anatis were 

 found mating, and an egg-cluster of the former species was also 

 discovered. 



The aphid eggs were found hatching April 18, the young lice at 

 once proceeding to the leaf buds, which were just beginning to burst 

 open. The development of foliage was considerably retarded by the 

 cold and wet weather which characterized the spring of 1898. 



Larvae of Adalia were found May 1. At this time an excellent 

 opportunity was offered to observe the interrelations between several 



