338 ENTOMOLOGICAL NEWS. [Oct., igil 



While in California he did vakiable work in the suppression 

 of insect pests which were causing much damage, particularly 

 the scale insects and locusts. He discovered and perfected the 

 hydrocyanic gas treatment which is used to-day for the control 

 of most of the scale insects, by the fruit growers of California 

 and elsewhere. He also perfected a mash which successfully 

 checked the onslaughts of the locusts or grasshoppers in Cen- 

 tral California. It was through his careful thorough work that 

 the parasite of the cottony cushion scale was established to 

 destroy that pest. 



Since 1883 he contributed many papers on biological and 

 systematic Dipterology, especially the latter, which are inval- 

 uable to the students of North American Diptera. Among 

 these are papers on the Bombyliidae, Asilidae, Empididae, 

 Therevidae, Culicidae and Tachinidae which are monographs 

 or synopses of most of the genera and species of these fam- 

 ilies. His last paper of note, entitled "The Type-Species of 

 the North American Diptera" was completed a short time be- 

 fore his death, as the result of many years' study, and is of 

 the utmost importance to students of this order. His work 

 is to be classed with that of Loew and Osten Sacken in its 

 nnportance, and his connection with the U. S. National Mu- 

 seum as custodian of Diptera gave him the opportunity to 

 mvestigate and study along his special lines with the aid of 

 the best collection. The work of determining the great mass 

 of material received by the Museum, gave him little time to 

 devote to the descriptions of new forms, so that we are now 

 complaining of his short diagnoses. He described over 1000 

 species from North America and many from other parts of 

 the world. His views regarding the limits of species, and on 

 nomenclature were very conservative, and no amount of favor, 

 sentiment or criticism would influence him in his opinions. 

 That he was one of the greatest American Dipterists there 

 is no doubt, and there are few if any who can fill his place 

 as well as he did. He was a member of the Washington 

 Academy of Science, the Washington Entomological Society 

 (its president 1903-1904), the Entomological Society of 

 America, the Association of Economic Entomologists, and the 

 American Association for the Advancement of Science. — E. T. 

 C, Jr. 



