76 | NEUROPTERA. 
4. Argia mesta. (Tab. IV. figg. 20, 29, 29s.) 
Agrion mestum, Hagen, Syn. Neur. N. Am. p. 94 (1861) *. 
Argia mesta, Selys, Bull. Acad. Belg. (2) xx. p. 384 (1865)°. 
¢. Rear of the head chiefly black or dark brown. Pale antehumeral stripe one-half as wide as the dark 
mid-dorsal stripe. Humeral stripe a line, uniting below with a wide mesepimeral band which reaches up 
to the base of the front wings. Segment 2 mostly blackish, with 1 mid-dorsal yellow line; 3-7 blackish, 
with a narrow, transverse, basal, yellow ring, and a fine, longitudinal, mid-dorsal, yellow line; 8 and 9 
tawny, with a black spot or longitudinal stripe each side from the base to two-thirds of the way to the apex, 
and the inferior margin blackish. 
Qlder males have relatively less extended pale colours, and later become pruinose on the head, thorax, and 
base and apex of the abdomen, thus concealing the original coloration. 
The metepimeron and adjoining part of the metepisternum are blackish, while in A. putrida (d) the same 
areas are pale. 
G. Differs from the male as follows :—Rear of the head tawny, with a varying amount of black. Thoracic 
dorsum pale (tawny or green), mid-dorsal and humeral stripes reduced to mere lines. Segment 2 pale 
greenish, each side with a blackish longitudinal stripe (dilated at the hinder end) or anteapical spot; 
3-7 pale brown or green, a longitudinal black stripe on each side for almost the entire length of each 
segment, except at the base; 8 as in male; 9 pale green or brown, with or without a superior longitudinal 
brown stripe on each side as long as the segment or only in its basal half. 
In some females (e.g., from Linares), although somewhat pruinose on the pectus, segments 6, 7, and 8 are 
almost devoid of dark markings. 
& ©. Pterostigma of the front wings, 1:18 ¢,1:25 mm. Q long, surmounting more than one cell (97°5 °/, 6, 
98 °/, 2) or one cell (2°5 °/, 5,2°/, 9). Pterostigma of the hind wings 1-4 ¢ 2 mm. long, surmounting 
more than one cell (99 °/, ¢, 98°/, 2) or one cell (1°/, 5, 29/5 @). 
Antenodal cells on the front wings 4 (82 °/, 5d, 92°/, 92), 5 (15% b,8°%/o.9), 4+ (15 °/, 3), or 
3 (15 °/, 3); on the hind wings 4 (87°5 °/, 3, 845 9/, 2 ),5(2°5 Jo 5, 45°, 2), 8+ (1%, 5, 2/6 2), 
or 3 (92/4 5, 9%o 2). 
Dimensions.—Abdomen, ¢ 35-37, 2 31-385; hind wing, ¢ 24°5-27°5, 9 25-28 mm. 
ITab. Unitep States, Pecos River! ?, Dallas (M. C. Z.: 1 2) and Round Mt. (colls. 
P. P.C. and J.G. Needham: 8 , 42) in Texas, Arizona (C. U. lot 35, M. C. Z.: 
2 6,1 2).—Mexico, Nuevo Laredo in ‘lamaulipas [4 ¢, 2 2 ], Montemorelos [5 ¢, 
1 ?], and Linares [2 ¢, 2 2] in Nuevo Leon (Barrett, coll. P. P. C.). 
The mesostigmal lamina of A. ma@sta, 2, is often not visible, being hidden by the 
hind lobe of the prothorax. 
A, putrida, Hagen, of the United States, differs apparently in colour only, and should 
probably be regarded as a variety of A. mesta, this name having a priority of one page 
in Hagen’s work. 
6. Argia translata. (ab. IV. tigg. 18, 30, 30 s.) 
Argia translata, Hagen, in Selys, Bull. Acad. Belg. (2) xx. p. 410 (1865)'; Calvert, 27th Ann. 
Rep. New Jersey State Board Agric., Suppl. p. 68 (1900) *. 
dg. Rear of the head black, often with yellow along the eye-margins. Pale antehumeral stripe from one-third 
(in younger) to one-twelfth (in older males) as wide as the black wid-dorsal, or absent altogether in old 
individuals. Humeral stripe in younger males divided for almost its entire length, except at.its lower 
end, into two, of which the anterior is the humeral stripe proper and is narrower than the pale ante- 
humeral; the other is mesepimeral and is as wide as, or wider than, the pale antehumeral; with 
age these two fuse so as to be even five times wider than the pale antehumeral. Segment 2 
plack, each side with a pale inferior stripe, and in younger males a pale mid-dorsal stripe or spot; 3-7 
