THE CANADIAN ENTOMOLOGIST 117 



Explanation of Plate hi. 

 Figures 2. 4. 5, 6, 8. 9. and 10 are based on figures by Escherich. Figures 

 1 and 7 are based upiiu figures by Patcb. l'>09. 

 Fig. 1. . .Right hind wing of Aphid Macrosiplium sohinifolii. 

 Fig. 2... Right fore wing of Psocid Embidotroctcs paradoxus. 

 Fio- 3. . Riffht hind win? of Zorapteron Zorotxpiis snvdcri. 

 Fie 4. . .Rig-ht fore wing of Psocid Embidopsocus luteiis. 

 Fie. 5. . .Right hind wing of Psocid Arcliipsociis rccc}is. 

 'Fi'y. 6. . .Rio-ht hind wing of Psocid Psxllipsocus ramburi. 

 Fig. 7. . .Right fore wdng of Aphid Pamphigus vcnafnsciis. 

 Fig. 8... Right fore wing of brachypterous form of Psocid Archipsocus brasil- 



ianii.'i. 

 Fig-. 9. . .Right fore wing of Psocid Archipsocus rcccns. 

 Fig. 10. Right fore wing of Psocid Archipsocus brasilianus. 

 Fig. 11.. Right fore wing of Zorapteron Zorofypus hubbardi. 

 Fig. 12.. Right fore wing of Zorapteron Zorotypus snydcri, after Crampton, 



1921. This wing should be of same size as that of the Zorapteron 



shown in Fig. 11. 



TWO NEW CANADIAN MA\ FLTKS (EPHEMERIDAE). 



BY J. MCDUNNOUGH, PH. D. 

 Entomological Branch, Ottawa. * 



In the second week of June, 1920, I collected from the underside of the 

 leaves of an ash tree, situated near the banks of the Rideau river a number of 

 specimens of both sexes of those tiny May flies belonging to the genus Bactis. 

 At the time I supposed I was collecting Bactis pygniaca Hagen, but a careful 

 study of the entire material at a later date convinced me that three species were 

 represented and could be fairly readily distinguished, even in a dried condition, 

 by the relative size of the superior, reddish portion of the eyes. 



It became necessary therefore to determine whether the true pyguiaca 

 was represented in my catch and specimens of all three species were submitted to 

 Dr. Nathan Banks of the Cambridge Museum. Mass. Dr. Banks was kind 

 enough to compare these specimens carefully with the remains of the ty])e $ of 

 B. pyguiaca (one wing and a portion of thorax) as well as with the type $ of 

 B. uuicolor Hagen and co-types of B. propiuquus Walsh. ( )ne of the species 

 he definitely identified as propiuquus. the other two he reported as probably 

 new, both being considerably larger than pygmaea and showing constant differ- 

 ences in venation, notably in the hinder portion of the wing. 



Uuicolor was described from $'s only, collected in Washington, D. C, and 

 until the correct J*'s can be definitely associated with the opposite sex, identifi- 

 cation of this species must remain doubtful. The same is more or less true of 

 pyguiaca; the type locality is given as "St. Lawrence River" and until we have 

 more definite knowledge of the Bactis forms inhabiting this river, it would be 

 mere guess work, in view of the very close superficial resemblance between the 



* Contribution from the Entomological Branch, Dept. of Agriculture, Ottawa. 



