FLIES OF THE GENUS ODINIA — SABROSKY 231 



1933, and various dates from June 7 to July 21, 1934. The paratype 

 from Strong, Maine, is labeled "Ex logs Betula papyrifera'' ; all other 

 Maine specimens in the type series are labeled "Ex logs Betula pa- 

 pyrifera inf.[ested] by ambrosia beetles -\-Agrilus anxius." The 

 Quebec specimens emerged in cages placed over felled white and black 

 spruce, balsam, and white birch attacked by various beetles. 



This species is close to maculata Meigen as defined by Collin (1952), 

 but the latter is a much darker species, with the first and second 

 antennal segments predominantly brownish or black, the dark area 

 on third antennal segment extending to base of segment on outer 

 surface, the thorax with narrow brown stripe on the midhne and in 

 each dorsocentral position, a distinct supraalar stripe, and the scutel- 

 lum somewhat brownish about the middle. One European female 

 before me, agreeing with Collin's diagnosis, is easily distinguished 

 from the North American species. 



Collin (1952, p. 116) refers to the association of 0. ornata (Zetter- 

 stedt) Avith Betula, and beheves that it will probably prove to be 

 a distinct species when the type specimen has been studied. How- 

 ever, since the original description states that the basal antennal 

 segments are black, it does not appear that the name ornata need 

 concern us in connection with the Nearctic species found in association 

 with Betula. 



5. Odinia meijerei Collin 



Odinia meijerei Collin, 1952, Proc. Roy. Ent. Soc. London, ser. b, vol. 21, pp. 112, 

 115 (England, Netherlands). 



Limited European material of meijerei is available for comparison, 

 but from this it appears that the species also occurs commonly in 

 North America. 



The detailed description given above for biguttata will serve well 

 for meijerei, the chief difference being that the latter has the first 

 two antennal segments, or at least the first, predominantly or entirely 

 black, mesonotum chiefly gray pollinose, upper mesopleuron and 

 pteropleuron with a broad brown stripe, marginal ceU clear and un- 

 spotted, and membrane not clouded about the apices of second and 

 third veins (fig. 5) . The front is broad, slightly over twice the width 

 of an eye and slightly over half the width of the head. The antenna 

 in meijerei is notably larger and darker in the females than in the males. 

 The mid tibia has two apical ventral bristles but the posterior is 

 clearly shorter and weaker than the anterior. 



Over 40 specimens are before me, chiefly from several localities in 

 New York and Pennsylvania, reared in connection with studies on 

 forest insects. Other available specimens are from Midland Co., 

 Mich., June 11, 1939, R. R. Dreisbach (USNM); Dauphin Co., Pa., 

 May 3, 1897 (USNM); lower Westchester Co., N. Y., May 22, 1934, 



