EPHEMERINa:. 551 



Ephemera viridescens, Barnston's MSS. 



Grayish brown, testaceous beneath excepting the disk of the 

 pectus : antennae black : hinder part of the thorax with testaceous 

 borders: abdomen scabrous, more than twice the length of the 

 thorax ; the two last segments with a testaceous stripe on each side : 

 setae testaceous, pubescent, shorter than the abdomen : legs testa- 

 ceous : wings grayish ; veins black, testaceous at the base ; longitu- 

 dinal veins about twelve in number, differing much in structure 

 from those of P. lata; transverse veins numerous and distinct: 

 hind-wings with brown hind borders. Length of the body 9 lines ; 

 of the setae 8 lines ; of the wings 24 lines. 



a. St. Martin's Falls, Albany River, Hudson's Bay. Presented by 

 Dr. Barnston. 



12. Palingenia occulta. 



Testacea ; antenna nigra; mesothoracis latera fusca ; abdomen 

 fusco bivittatum; seta corporis longiiudine ; tarsi et -pedes 

 antici subfusci ; alee subcinerea. 



Testaceous : antennae black, testaceous at the base : mesutho- 

 rax brown on each side : abdomen darker than the thorax, with 

 two irregular brown stripes : setae dark testaceous, minutely pubes- 

 cent, as long as the body : legs testaceous ; tarsi and fore-legs 

 brownish: wings grayish ; veins black, testaceous at the base : fore- 

 wings pale yellow at the base ; fore border slightly tinged with 

 brown. Length of the body 9 — 11 lines; of the setae 8 lines ; of 

 the wings 18 — 22 lines. 



a — c. Arctic America, between Lake Winipeg and Lake Superior. 

 Presented by Sir John Richardson. 



13. Palingenia natata. 



Fusco-testacea ; antenna nigra ; abdomen fusco bivittatum ; seta 

 fulva, fasciata, hirsutissima, corpore paullo breviores ; pedes 

 testacei, tibiis tarsisque fuscis; ala subcinerea, venis nebu- 

 losis, antica nigro maculatce. 



Ephemera natata, Barnston, MSS. 



3b 2 



