SMITHSONIAN MISCELLANEOUS COLLECTIONS. 



178 



CIECULAR TO ECTOMOLOGISTS. 



The Smithsonian Institution proposes to publish a series of 

 descriptive monographs upon the dilTerent orders of North 

 American Insects, to follow its series of catalogues of known 

 species. 



In accordance with this plan, Dr. J. L. Leconte, of Philadel- 

 phia, is engaged in preparing an elementary work on the Coleop- 

 tera, to embrace descriptions of families, and an analysis of the 

 genera. Dr. Morris, of Baltimore, has nearly completed,a com- 

 pilation of all published descriptions of the DliwwdXLejndoptera, 

 to follow his catalogue of the species, now nearly through the 

 press. 



Dr. Henry Hagen, of Konigsberg, has undertaken a work on 

 ih&'Neuroptera ; Dr. Loew, of Meseritz, assisted by Baron Osten- 

 sacken, of St. Petersburg, is preparing one on the Diptera, and 

 Mr. H. de Saussure, of Geneva, one on the Hymenoptera. Each 

 of these will embrace descriptions of all the species before known, 

 besides several hundred new ones. 



The works on the Diptera, Neuroptera, and Hymenoptera, 

 will probably be issued within the year, and as it is very desira- 

 ble to have these as complete as possible on their first appear- 

 ance, the Smithsonian Institution would respectfully request full 

 series as can be furnished of specimens of these three orders, to 

 be transmitted to the authors mentioned. They should, as far 

 as practicable, be pinned, and inclosed in separate boxes, care- 

 fully packed, and endorsed with the names of the order, locality, 

 and collector, so that they can be forwarded without opening to 

 their destination. 



The Institution will endeavor to secure, if desired, the safe 

 return of any specimens that may be sent, although it would 

 request that several duplicates of each species be supplied, in 



