258 PHILIP p. CALVERT. 



c Hind wings with a dark brown, triangular, basal spot reaching backwards 

 to the apejc of the membranule. 9 with 8 not perfoliate. 



50. L<ibellula exusta Say. 



L. e. Say, Jour. Ac. Pliila. viii, p. 29, 1839. L. deplanata Eambur, Ins. Nevr. p. 

 75, 1842. Hagen, Syu. Neur. N. A., p. 154, 1861. L. julia Ubler {teste Hagen). 



Eeddish brown. Thorax with an olive or yellow antehumeral stripe. Abdomen 

 with a mid-dorsal black stripe. Wing-bases yellowish. Front wings with two 

 dark brown basal streaks. Hind wings with a superior basal streak and an inferior, 

 triangular, basal spot of varying size, dark brown, distal ends of these two some- 

 times united. Thorax and abdomen white pruinose in old males. • 



Abd. % 22-27, 9 20.5-24. H. w. % 27-33, 9 26.5-32.5. 



Atco,N. J.,Jiine4, 18,C.W. Johnson (W. L, A. E. S., C). One 

 female, Pa. (A. E. S.) 



Maine and Massachusetts to Vancouver's Is. ; New Jersey, Penn- 

 sylvania, Georgia. 



N. B.— Dr. Hagen states (Proc. Bost. Soc. N. H. xviii, p. 69), " L. deplanata 

 seemed to be a dwarfish southern form [of exusta,'] but there are differences in 

 the genital parts, probably important enough to separate the two species." 

 Thanks lo the kindness of Mr. Samuel Henshaw, the writer has examined draw- 

 ings of the appendages of male and female of exusta and deplanata contained in 

 the Museum of Comparative Zoology at Cambridge, Mass. A comparison of 

 these drawings with specimens in his own collection does not reveal differences 

 constant enough to serve as specific. 



51. Liibelltila qiiadrimaculata Linne. 



L. q. Linne, Syst. Nat. i, p. 543, 1758. Hagen, Syn. Neur. N. A., p. 150, 1861. 



Olive or yellowish. Humeral and second lateral thoracic sutures black with 

 adjacent inferior brighter yellow marks; a bright yellow spot each side of 2-9. 

 dorsum of 6-10 blackish. Wings yellow at base or along front margin, and a 

 small black nodal spot ; hind wings in addition with a black, basal, triangular spot 

 below the submedian vein and filling the triangle, thence running obliquely to 

 the anal margin a little beyond the apex of the membranule ; this spot veined 

 with yellow. Var. prenubila has a brownish cloud beneath the pterostigma. 9 

 App. a little longer than 9. 



Abd. l 26-31, 9 27-31. H. w. % 33-36, 9 34-36. 



Atco, N. J., June 18, C. W. Johnson (W. I., A. E. S., C). 



Nova Scotia to Massachusetts, west to Washington and northward; 

 New Jersey, Illinois, Utah, Wyoming ; Europe (except the Medit- 

 terranean Is.), Northern and Central Asia, Asia Minor. See p. 206. 



d. Hind icings at least with a longitudinal basal stripe {ivhose hind margin lies 

 at least as far back as the postcosta), a nodal spot extending half across 

 the wing, and a band crossing the wing at apex or at pterostigma — all 

 three dark brown or reddish brown. 9 with 8 perfoliate. 



^*i. Liibellula seinifasciata Burmeister. 



L. s. Burm., Handb. Eut. ii, p. 862, 1839. Hagen, Syn. Neur. N. i ., p. 151, 1861. 



