1915] Dohanian — H.r/ernal Anatomy of Boreus hrumaUs Filch 121 



the fact that very Uttle is known about its habits and that it has 

 never been carefully figured. To fill this want and to avoid such 

 confusion in the identification of the members of this genus, as 

 has recently occurred among a group of amateur entomologists in 

 Germany,^ the writer has undertaken to figure B. hrumalis Fitch 

 as carefully as possible and to redescribe it from the many speci- 

 mens available, particularly as these show certain variations from 

 the original description of Fitch. 



The genus Boreus, first described by Latreille in 1825, contains 

 ten or eleven recognized species. Of these only four are to be 

 found in the United States, two in the eastern and two in the west- 

 ern parts of the country. The remaining ones are distributed over 

 Europe and Asia. 



Boreus hrumalis was described many years ago by Asa Fitch 

 (1847), accompanied by some notes on its occurrence in New York 

 state. At the same time he described a second species, B. nivori- 

 undus. Fitch's paper contains the first reference to the occurrence 

 of Boreus outside of Europe. Both of the above species are to 

 be found in New England, as there are in the collection of the Bos- 

 ton Society of Natural History specimens- from Jackson, N. H., 

 Medford, West Roxbury and Stoneham, Mass., to which should 

 be added also Weston and Jamaica Plain, Mass. 



The life history as yet has not been worked out completely for 

 any of the species of the genus, but they are all believed to be 

 predacious on other winter insects and also those found hibernating 

 under mosses, stones, etc. Friedrich Brauer, having found some 

 larvae of B. hyemalis L. in moss in 1856, believes that the life cycle 

 covers a period of one year: the imago appears about the middle 

 of October and remains in the adult state through the w inter until 

 April of the following year; early in the summer, about June, the 

 larvae hatch, undergo a rapid development, and remain in the full 

 grown condition until the end of the summer; then they pupate 

 and emerge as adults very soon thereafter; these are at first rather 

 pale-colored and immature, an observation which is corroborated 

 by both Dalman and Stephens from immature adults that were 

 found by them in England under stones and moss (Westwood: 

 Introd. Mod. Class. Ins., II, p. 54). 



" Entomologisches Jahrbuoh fiir 1915, 24 Jahrgang, pp. 141-143. 



* Mr. C. W. Johnson very kindly loaned these specimena to the writer. 



