1863.] 
na scarcely as long as tlie 9th ventral, very wide, emarginate at tip in the 
form of a circular arc 45° long, the emargination almost attaining its base. 
Legs rather paler than the body; tibiae with a superior yellow vitta ,• tarsal 
claws obfuscated. All four wings hyaline and marked alike, their extreme tips 
slightly clouded with fuscous, their veins black except the costal vein which is 
pale-reddish-brown, and the subcostal and median veins which are brown. 
The pterostigma, a square spot upon each of the second series of antecubitals 
narrower towards the nodus in the front wing, and a large irregular spot upon 
the nodus, all pale-reddish-brown. Both membranules white at base, fuscous 
at their extreme tip. Front wing, antecubitals 7, postcubitals 8 ; hind wing 
antecubitals 5, postcubitals 8. Discoidal areolets both before and behind 2—3, 
commencing always with 3. Total length including appendages 53 mill. Exp. 
74 mill. Abd. 36J mill. Abd, appendages 2^ mill. Front wing 37i mill. Its 
breadth 10 mill. Hind wing 38 mill., its breadth 13 mill. Hind femur 6;\ mill. 
Width of head 8i mill. 
One mature 9 only. Easily separated from all described N. A. Cor- 
dulia by the spots on the second series of antecubitals, which are sud¬ 
denly darker on their basal and terminal edges so as to appear to be 
bounded by cross-veins. 
It is with some misgivings that, in the absence of the % , I refer 
the above unique 9 to Cordulia, although it agrees in its general ap¬ 
pearance with the two species of that genus which I possess, and has 
the same short yellow pleural stripe enclosing the spiracle as C. late¬ 
ralis^ while its antecubitals and postcubitals are respectively 7 and 
8, and those of C. alhicincta 7—8 and 7—8. It seems to be per¬ 
fectly congeneric with my two species, except that the color is not 
“ brassy-green,” but the exact shade of olive found in Mesothemis cor- 
rupta Hagen, and the vulvar lamina, instead of being very long, cleft 
nearly to its base, and almost attaining the tip of joint 10, is unusually 
short as in Macromia. It cannot however be referred to Macromia 
nor to Didymops, because the tarsal claws are normal and not 
equally bifid, nor to Tetragoneuria, Selys, (a genus which I do not 
know,) for the reticulation is not more dense than usual, neither are 
the cellules generally square as the name (Tetra^o/mneuria ?) seems to 
imply. Possibly it may belong to Epitheca, the % of which genus has 
in reality a very small and scarcely perceptible obtuse anal angle to 
the hind wings, apparently overlooked by authors, and a membranule 
no larger comparatively than in Cordulia, so far as I can see, though 
it is stated to be “ large”; but in that genus too the vulvar lamina is 
long and bifid, extending to the tip of joint 9, and the only described 
