BRECHMORHOGA. . 281 
each about -7 mm. wide; abdomen dark brown, becoming blackish posteriorly, with the following pale 
green or yellowish markings: one on each side of segment 1, three on each side of 2, a longitudinal stripe 
on each side of 3-7, broken into a shorter anterior and a longer posterior piece on 3-5, reduced to a mere 
vestige on 6, on 7 slightly less than half as wide as the side of the dorsum on which it lies, a transverse 
basal line on each side of 3 (see p. 279). 
Front wings with 12-14 ante-, 6-9 (usually 7) posteubitals; hind wings with 8-10 (usually 9) ante-, 7-10 
postcubitals. Of 50 ¢$ hind wings, 36 (or 72 °/,) had a (one of them two) single cell reaching the entire 
distance from short sector to first sector of the triangle just distal to the triangle; of 36 2 hind wings 
but 1 (2°8°/,) had such a cell, leaving 14 ¢ 35 9 hind wings in which the two post-triangular rows 
begin immediately at the triangle ; this difference in the males is not correlated with locality, and is 
often asymmetrical, as in the female concerned. The ? from Trece Aguas has the apices of the front 
wings brown inward to the 4th postcubital. 
3. Abdomen considerably narrower at the base of segment 4 (1 mm.) than at 2 (25-3 mm.), thence gradually 
widening to 8 (1:8 mm.), 10 narrower. 
Superior appendages 2 mm. in length, not so long as segments 9 and 10, longer than 9, of a form very similar 
to that already figured for mendazx (q.v.), with about nine inferior denticles on the third fourth. 
Q. Abdomen gradually narrowing from segment 2 (3 mm.) to the base of 6(1-1°5 mm.), thence widening to 9 
(2:5-3 mm.), 10 narrower. Appendages 1 mm. long, longer than segment 10, not so long as 9. 
Hab. Mexico, Jalapa (Hay, U. S. N. M.: 1 3), Atoyac (H. H. Smith, Schumann: 
16 3, 17 9), Tuxtla (Barrett, coll. P. P. C.: 1 3), all in Vera Cruz; Guatemata, 
San Felipe (Maxon & Hay, U. S. N. M.: 1 6), Mazatenango [1 9 ], Santa Lucia 
[2 2], Escuintla [2 9] (Williamson, coll. ejusd.) (Hine, O. 8. U.: 1 2), Zapote 
(Champion, 43,12), Trece Aguas in Alta Vera Paz (Barber, U. S. N. M.: 1 2); 
Costa Rica, Carrillo [1 3 ], Puriscal [1 ¢ ], San José [1 ¢, 1 2 ] (Underwood) (Biolley : 
1 2), Caché (Rogers: 2 3), Bkistebu, Diquis Valley (biolley, coll. Adams: 1 3); 
Panama (coll. McLachlan: 1 3). 
Taken in January and February (Guatemala, Bkistebu), March (S. José), April and 
May (Atoyac), August (Jalapa, Tuxtla), and October (S. José). 
Of the specimens taken at Escuintla, Jan. 31, 1905, Mr. Williamson noted: “ Ovi- 
positing in rapids. Flight very swift and Gomphine- or Corduline-like, close to the 
water and following the shore.” 
B. vivax is much like precor, and formerly I confused the two species. Their 
differences are given on page 2/9. They occur together in some localities at the same 
time, ¢. g. Atoyacin May, S. Felipe (vivax Feb. 22, precox Feb. 23, 1905), Mazatenango 
(Feb. 3), Santa Lucia (vivax Jan. 31, Feb. 2, precox Jan. 31, 1905), Zapote. 
2. Brechmorhoga precox. (Tab. VIII. fig. 49.) 
Dythemis precox, Hagen, Syn. Neur. N. Amer. p. 164 (1861) '; Kirby, Cat. Odon. p. 34 (1890) ”. 
Brechmorhoga precox, Calvert, Proc. Bost. Soe. Nat. Hist. xxviii. p. 315, t. 2. figg. 25, 29 (spot 
on 7, vulv. lam. 2 type) (1898) * (type ? only). 
The type of Hagen, a female, has the abdomen 37 mm., the hind wing 33 mm. in Jength. Mr. Henshaw, with 
his usual kindness, has recently re-examined the type for me and writes that it has two rows of cells 
increasing to three posteriorly on the hind wings between A, and the anal margin, and that the markings 
on abdominal segment 3 are confluent, as stated on page 279. 
The following notes based on the material from Gualan, all taken between Jan, 11 and 23, 1905, indicate the 
