No. 64] DIPTERA OF CONNECTICUT I TAXONOMY 175 



Key to Families 



C. H. CURRAN 



American Museum of Natural History- 

 New York 



In view of the fact that there are very few families of North 

 American Diptera that do not occur in Connecticut the following 

 ke}'- contains all of the families at present known from this continent. 

 It differs only slightly from the key published in "The Families and 

 Genera of North American Diptera," the family Cryptochaetidae 

 being added, and the Asteiidae being shifted to a position where it 

 is more readily separated. 



It must be recognized that restriction of families and the group- 

 ing of genera together depends to a very large degree upon the per- 

 sonal opinions of those who have spent many j^ears studjang insects 

 and that because of human frailties it is very seldom that tAvo author- 

 ities will agTee in all respects. There are some students wlio would 

 divide the order into many more families than I recognize while others 

 would reduce the number. The future may result in the recognition 

 of many more families since the present tendency is to "split". In 

 actual practice the number of families recognized is really of little 

 importance provided we can determine our specimens with the least 

 amount of eii'ort. There can be little doubt that too great "splitting" 

 makes the determination of specimens more difficult. It would seem 

 to be best to place two or more igroups of genera together under a 

 single family name than to recognize them as distinct families that 

 can be separated only with difficulty and sometimes with doubt. If 

 the genera concernecl are grouped together it is, on the face of it, 

 much easier to run them through a single key than to worry for hours 

 as to whether they have been assigned to the proper family by the 

 worker, who may be entirely unacquainted with the group of flies 

 for one or more of which he is attempting to find a name. This ques- 

 tion has been put very concisely by many entomologists in the fol- 

 lowing words : "I like to know a syrphid when I see one." It might 

 well refer to a tachinid, a tabanid or any other family. 



On another point there may be disagreement. This has to do 

 with the formation of family names. There are some entomologists 

 who claim that the name is to be formed from the "root" of the family 

 name. As an example of this we may take Dolichopus which, from 

 the "root", becomes Dolichopodidae. If we adhere to the "Inter- 

 national" rules this spelling is wrong since family names are to be 

 formed by dropping the final vowel and following consonants and 

 adding idae — the family designation. From the viewpoint of the 

 Latni scholar this latter method may be outrageous but to the aver- 

 age student of entomology it is a simple, clear rule that can be 

 followed without difficulty. It also has the advantage that it means 

 fewer letters on a label and does not require a knowledge of ancient 

 languages in order to determine the proper ending of a family name. 



