264 PHILIP p. CALVEKT. 



N. B. — The specimens of semicincta from Nevada, Colorado aud Califoruia, 

 have black stripes on the humeral and lateral thoracic sutures, which are absent 

 in those from Pennsylvania. 



62. Diplax viciua Hagen (PI. II. fig. 4). 

 D. V. Hagen, Syn. Near. N. A., p. 175, 1861. 



Yellowish (teneral) to red; lateral margins of 3-9, and frequently a mid-dor- 

 sal stripe on 8 and 9, blackish brown. Extreme base of wings yellow. Legs 

 yellowish to reddish. 



% . Hamule bifid in its apical two-thirds, branches of nearly equal length, both 

 almost erect, internal (anterior) branch more slender, apes acute : external branch 

 two to three times wider, apex rounded. Genital lobe projecting slightly farther 

 ventrally than the hamule. 



9. Vulvar lamina distinctly projecting, its margin entire. 



Abd. 1 20.5-23.5, 9 20.5-23.5. H. w. % 22-25, ? 21.5-24. 



Very abundant around Phila., July 11 — Oct. 26, and probably 

 later; in copula or ovipositing Aug. 31, Sept. 3, 10, 19, 21, Oct. 11, 

 12, 24. 



Maine to Virginia ; Ontario, Illinois (Miss Wadsworth, Harvey, 

 Richardson). 



B. An additional transverse carina on 4. 



63. Diplax corrupta Hagen. 



Mesoihemis c. Hagen, Syn. Neur. N. A., p. 171, 1861. 



Olive or brown ; face, an antehumeral stripe, two lateral thoracic stripes, white 

 or yellow. Abdomen yellowish, spotted with white and brown, 8-9 with a mid- 

 dorsal black spot. Wing-veins yellowish. Pterostignia yellow, brown in the 

 middle. Legs black, femora and tibise with a superior yellow stripe. 



% . Hamule with apical third bifid, internal branch short, slender, apex acute, 

 curved outwards to form a hook ; external branch twice as long, much thicker, 

 directed outwards and backwards, apex blunt. Genital lobe projecting a little 

 farther ventrally than the external hamular branch. Sup. app. yellow, thickened 

 in their apical half, with a row of 9-14 inferior, black denticles. 



9. Vulvar lamina not projecting, apex emarginated. 



Abd. % 24.5-28.5, 9 25-29. H. w. % 27.5-31, 9 28-32. 



One male, Folsoni, Del. Co., Pa., Oct. 3, 1889, P. P. Calvert (C). 

 Pennsylvania; Illinois to California, Montana to Mexico; Ochotsk. 



37. Peritheinis Hagen. 



Hagen, Syn. Neur. N. A., p. 185, 1861. Kirby, Trans. Zool. Soc. Loud, xii, p. 

 273, 1889. 



64. Peritheinis doniitia Drury. 



Libellula d. Drury, 111. Exot. Ent. ii, p. 83, pi. 45, fig. 4, 1773. P. d. Hagen, /. c. 

 p. 185, 1861. 



Yellowish brown. Thorax sometimes with two lateral yellow stripes of vary- 

 ing width. Abdomen with some yellow marks. 



