AMERICAN DIPTERA. 267 



STUDIES IN NORTH AMERICAN DIPTEROLOGY : 

 PIPUNCULIDtE. 



BY E. T. CRESSON, JR. 

 Plates V-IX. 



This paper is the result of about two years interrupted 

 study of this little known family of Diptera. Unknown to 

 either of us, Mr. Nathan Banks had also been doing some 

 work with the genus Pipunculus ; but upon discovering that 

 I had also been working on the same group with much more 

 material at hand, he kindly turned over to me his collection 

 and descriptions of some forms he considered new. These 

 latter I give in this paper as " Banks, n. sp." accompanied 

 by my own observations upon the types. The collection 

 before me for study composes, besides that already at the 

 Academy of Natural Sciences of Philadelphia, the material 

 loaned by Mr. C. W. Johnson of the Boston Society of 

 Natural History, which, upon addition of that of Mr. Banks, 

 makes a sum total of 216 specimens, of which I find 31 

 known species and 31 which I consider new. 



My first attempt in the study of this group of insects was 

 in endeavoring to determine a few specimens in the collec- 

 tion here in Philadelphia. I found most of them unde- 

 scribed, but hesitated to describe them as new upon such 

 small amount of material at hand. Mr. Johnson then offered 

 me the loan of the undetermined material in his own collec- 

 tion and in that of the Boston Society of Natural History, 

 and so my humble attempt has emerged into an undertaking 

 far beyond my expectations. I regret the inability of giving 

 a more exhaustive treatise on the subject, but the pressure of 

 work on another paper I had already begun makes this im- 

 possible. Still it is hoped that this contribution will be an 

 incentive to some other student, who can give the subject a 

 more monographic treatment ; for by special collecting, breed- 

 ing and the borrowing of all the available material, one should 



TRANS. AM. ENT. SOC, XXXVI. (34*) DECEMBER, 1910. 



