NOTES ON THE FLIES OF THE GENUS PSEUDODINIA, WITH 

 DESCRIPTION OF A NEW SPECIES. 



By J. R. Malloch, 



0/ Urhana, Illinois. 



In a synopsis of the genera of North American Agromyzidae in 

 1913 ^ I included the genus Pseudodinia in Octhiphilinae. I did so 

 because I considered that the species had closer relationship to 

 Octhiphila than to any other genus, and this view I still hold. Me- 

 lander, in his synoptic review of Agromyzidae and Geomyzidae,- has 

 placed the genus in Geomyzidae. From his own tables I gather that 

 the reason for this can only lie in the presence of the mesopleural 

 bristle and the color of the species. At least these are practically 

 the only characters which prevent one using the subfamily key given 

 by Melander from placing the species where they obviously belong. 

 It is not necessary that I should lay stress upon the fact that neither 

 of the characters above mentioned are of subfamily value. On page 

 225 of Melander's paper is given a tabulation of characters for the 

 separation of the families Agromyzidae and Geomyzidae from allied 

 families. In the first column it is indicated that the costa in Geomy- 

 zidae is once broken. Pseudodinia has no costal break, as is indicated 

 in the generic table given in a subsequent part of the same paper. It 

 is unnecessary that I should enter into a lengthy discussion as to the 

 generic position of Pseudodinia, but in closing I may perhaps more 

 readily impress upon the students the fact that the genus bears more 

 than a passing resemblance to OctliipTiila by stating that Coquillett, 

 who described the genus, made the mistake of labeling a specimen in 

 the United States National Museum collection "OctMpliila n. sp." 

 This species I labeled provisionally "Pseudodinia pruinosa n. sp." 

 but afterwards refrained from describing it because of certain facts 

 subsequently discovered from an examination of a series of speci- 

 mens in another collection. 



The table given in my paper previously referred to will serve to 

 correctly place the species of this genus generically. The species 



1 Proc. U. S. Nat. Mus., vol. 46, 1913, pp. 127-154. 



2 Journ. New Jersey Ent. Soc, vol. 21, 1913. 



Proceedings U. S. National Museum, Vol. 49— No. 2101. 



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