80 NEUROPTERA. 
from every month in the year, but nothing is known as to how continuous its appear- 
ance may be in any given locality. 
Considerable variation exists, even in individuals from the same locality, as to the 
degree to which the tip of the superior appendage of the male is bifid, and in the 
acuteness of the outer branch of the same. ‘The shape of the inferior appendage, seen 
in profile, is especially characteristic of this species. 
The mesostigmal lamina of the female is small, similar in shape to that of 
A. agrioides (Tab. IV. fig. 26). 
9. Argia ulmeca, sp.n. (Tab. IV. figg. 9, 34, 34s, 347.) 
i. Rear of the head black, a pale stripe along the eye-margins. Pale (blue or violet) antehumeral stripe 
from three-fifths to two-fifths as wide as the black mid-dorsal. Humeral stripe forked at its upper end 
in younger males; at mid-height from two-thirds as, to slightly wider than, the pale antehumeral. 
Segment 2 black, an oval, dorsal, blue or violet spot in the basal two-thirds, and each side with a pale 
inferior stripe; 3-7 black, with a transverse, basal, blue ring, prolonged on 3 to the middle or to two- 
thirds the length of the segment, and on 4 to from one-sixth to one-third its length; 8 and 9 blue, each 
side with an inferior black stripe as long as the segment, or absent in the basal fourth; oceasionally 
8 has also a pair of black anteapical dorsal spots. 
9. Differs from the male as follows:—Humeral stripe forked. Blue mid-dorsal prolongation on segments 
3 and 4 sometimes reaching to three-fourths the length of these segments, or on 4 sometimes 
not more than a line, and a trace of such a line on 5; 7 in some specimens with an inferior yellow line 
each side; 8 and 9 luteous(?), each side with an inferior black stripe as long as the segments and 
a superior black band on the basal two-thirds or half, all four of these being confluent at the base of 
each segment. 
3 Q. Pterostigma of the front wings 1:1 mm. long, surmounting more than one cell (92°3°/, ¢, 100 °/, 2) or 
one (7°6 °/, 3); of-the hind wings 1:1—1-25 long, surmounting more than one cell (100 °/, ¢ @). 
Antenodal cells on the front wings 4 (77 °/, ¢, 96 9/, 2), 5 (23 °/, 5), or 34+ (49/5 2); on the hind wings 
4 (100 °/, 3, 88°, 9) or 3 (12%, 2). 
Dimensions.—Abdomen, $ 32°5-35°5, 2 29-5-32; hind wing, ¢ 23°5-26, 2 235-25 mm. 
Hab. Mexico, Chavarillo j(Barreti, coll. P. P. C.: 26,1 2) and Atoyac (Schu- 
mann, H. H. Smith: 7 3,12 9) in Vera Cruz, Acaguizotla [1 3] and Rincon in 
Guerrero [2 ¢ | (H. H. Smith); Honpuras, Rio Sarstoon (Blancaneaux: 1 ¢ ). 
_ Taken in April and May in Vera Cruz, in October in Guerrero. Resembles 
A. oculata to some extent. In addition to the differences given in the key, A. ulmeca 
possesses a longer pterostigma. The specific name is derived from the Ulmecs, a tribe 
said to have preceded the Toltecs in Mexico. 
10. Argia adamsi, sp.n. (Tab. IV. figg. 35, 35 a.) 
3. Rear of the head black. Pale antehumeral stripe one-third to one-fourth as wide as the black mid-dorsal. 
Humeral stripe one and a half times as wide as the pale antehumeral, forked or not above, reaching 
to the first lateral thoracic suture. Segment 2 blue, each side with a superior black stripe widened 
before the apex (which it reaches), but narrowed behind, united with its fellow by a very narrow, transverse, 
apical, black ring, and an inferior, ill-defined, blackish stripe; 3-7 black, blue at base, prolonged 
on mid-dorsal line on the basal four-fifths (on 3) to two-fifths (on 6), tapering posteriorly ; 8 and 9 
blue, each side with an inferior black stripe as long as the segment, 8 (in addition) with an isolated, 
mid-dorsal, black spot on the apical fifth. 
