Zool.— Vol. I.] CALVERT— ODONATA. 393 



distance of about one cell in the postcostal space, reticulation black, ptero- 

 stigma dark brown, surmounting one cell and parts of two others, outer end 

 more oblique than the inner, membranule dark brown. Front wings with 

 eleven antenodals, six to seven postnodals, triangle free, two post-triangular 

 rows increasing to three at the level of the origin of the subnodal sector, 

 internal triangle three-celled. Hind wings with eight antenodals, eight post- 

 nodals, triangle free, its inner side slightly nearer the base than is the arculus, 

 two post-triangular rows increasing. 



Dimensions: Total length 50 mm. ; abdomen 37 mm.; hing wing 32.5 mm. ; 

 pterostigma 2.5 mm. 



2 $ Tepic, Nov., 1894, Eisen and Vaslit. 



A male in the Museum of Comparative Zoology, Cam- 

 bridge, Mass., from Mazatlan, Mexico, October, 1873, by 

 Crotch, is evidently of the same species, but presents these 

 variations: a mere trace of metallic blue on frons and ver- 

 tex, entire free margin of labrum bordered with black, only 

 a median black spot on the median labial lobe, and the 

 inner edges of lateral labial lobes but very narrowly edged 

 with black, the two brown stripes on the sides of the thorax 

 fused together, pale spot on 7 a little more than half as long 

 as the segment, inferior appendage about one-fourth shorter 

 than the superiors, tip of hamule a little more slender, 

 internal triangle of right front wing with one cross-vein, 

 right hind wing with nine antenodals. 



Dimensions: Total length 47 mm.; abdomen 36 mm.; 

 hind wing 32 mm.; pterostigma 2 mm. 



The specific name postlobata refers to the posterior basal 

 tubercle on the genital lobe which is not possessed by any 

 other species of Brechmorhoga. 



29. Macrothemis pseudimitans Calvert. 



Macrothemis pseudimitans Calvert, Proc. Bost. Soc. Nat. Hist., Vol. 



XXVIII, 1898, p. 329, PI. II, fig. 35. 

 Macrothemis imitans Calvert, Proc. Cal. Acad. Sci., 2d Ser., Vol. IV, 



1893-94, P- 53i. PI- XVI, figs. 33, 35-39 (not of Karsch). 



The green colors of this female have been reddened by the alcohol. Tri- 

 angle of the left front wing with one cross-vein. Internal triangle of front 

 wings two-celled (right), three-celled (left). 



