294 NEUROPTERA. 
in ventral view less acutely pointed, anterior lamina and genital lobe subequally 
prominent ; female with the vulvar lamina bilobed, lobes digitate, subequal in 
length to the interval separating their tips. Abdomen, 3 24-27, ? 23°5-27; 
hind wing, ¢ 30-84°5, 9 29-35; stigma of front wing 2, of hind wing 1°5- 
7mm 2. ee eee ee ee ee ee 1, marcela. 
Supplementary sector next below the subnodal sector forming a loop with the latter 
and enclosing 3-4 cells on the front, 4-5 cells on the hind wings; front wings 
with 4-6 postnodals in the first series, 3-4 in the second series; hind wings 
with a basal brown area, veined with yellow, reaching to or into the triangle ; 
frons yellowish or greenish ; males with the lower edge of the superior abdo- 
minal appendages beginning to taper to the apex at 3 their length, inferior 
appendage in ventral view more acutely pointed, anterior lamina less prominent 
than genital lobe ; female with the vulvar lamina extremely short, widely and 
shallowly emarginated. Abdomen, 3 22-23, 219-23; hind wing, ¢ 27-28, 
9 28-28°5; stigma of front wing 1°5, of hind wing ] mm... . . . . . « 2. simplex. 
1. Miathyria marcella. 
Libellula marcella, Selys, in Sagra’s Hist. Cuba, Ins. p. 452 (1857) ’. 
Tramea marcella, Hagen, Stett. ent. Zeit. xxviii. p. 227 (1867); Proc. Bost. Soc. Nat. Hist. xviii. 
p. 66 (1875) °. 
Miathyria marcella, Carpenter, Journ. Inst. Jamaica, ii. p. 260 (1896) *; Kirby, Ann. & Mag. Nat. 
Hist, (6) xix. p. 600 (1897) °; (7) ili. p. 8363 (1899)°; Calvert, Proc. Calif. Acad. Sci. (3), 
Zool. 1. p. 888 (1899) 7; Prinzessin Therese, Berl. ent. Zeitschr. xlv. p. 259 (1900) °; Needham, 
Proc. U.S. Nat. Mus. xxvi. p. 709, fig. 4g (part of wing) (1903)°; Ris, Hamburg. Magalh. 
Sammelr., Odon. p. 34 (1904) ™. 
Tramea simpler, Hagen, Syn. Neur. N. Amer. p. 146 (1861) “ (teste Hagen *, nec Ramb.). 
Variable features independent of locality are the width of the mid-dorsal black on abdominal segments 5-10, 
the presence or absence of a yellow tint throughout the wings, and the extent of the brown basal area 
on the hind pair, The minimum for this last appears in females from Teapa (January, February) and 
Duran, in which the brown reaches out to A, only at the postcostal vein, and posteriorly only as far as 
the level of the “heel” of the anal loop; the maximum is presented by a female from Bonda, in which 
the brown extends out to the triangle in the submedian space (which is clear yellow in the middle 
between the cross-vein and the triangle), fills up the first postcostal cell between Cu, and A,, follows the 
proximal side of A, to the level of the middle of the triangle, and extends posteriorly to within -5 mm. of 
the hind margin at the point of greatest; width of the wing. Females from Altamira, Frontera, Guayaquil, 
and Batan (one from each locality) have the brown only a little less extensive. Males from Guadalajara, 
Guatemala (coll. McLachlan), and Duran (one from each locality) have the maximum extent of basal brown 
for that sex; the brown reaches to not more than ‘5 mm. beyond the origin of A,, which vein it borders 
proximally to not so far as the level of the triangle, and posteriorly stops at -5-1 mm. distance from the 
hind margin of the wing. These data modify some earlier statements ”” as to the wing-colouring. 
Younger individuals of both sexes have a nearly horizontal longitudinal yellow band, about 1 mm. wide, on 
the side of the thorax from the mesepisternum, just above the mesinfraepisternum, to the upper end of 
the metepisternum, and the metinfraepisternum and metepimeron yellow. With age these pale areas 
become brown and, in old males at least, eventually pruinose with the rest of the thorax. 
The examples from Ecuador tend to a greater length, but especially width, of the hind Wings, as may be seen 
from the following dimensions in millimetres :— 
