LEPTOBASIS.—AMPHIAGRION. 1 2 1 
Var. atrodorsum, var. n. 
3 @. Similar to Z. vacillans, the vertex darker, blackish, a small pale postocular spot (absent in Z. vacillans) 
on each side confluent with the pale colouring of the rear of the head ; prothorax pale yellowish in the 
young, black in older individuals ; thorax pale green, a mid-dorsal and a humeral stripe black, separated 
on each side by a pale green antehumeral stripe, which is one-third to one-fourth as wide as the mid- 
dorsal and one-half to three-fourths as wide as the humeral; abdomen yellowish or reddish-yellow, darker 
near the apex (¢ ) (the Tlacotalpam ¢ has the dorsum of 1 and of the basal half of 2 black), or with the 
dorsum of 1, of basal half of segment 2, of all of 5 and 6, of basal three-fourths of 7 black ( ¢ ). 
Dimensions— Abdomen, ¢ 26-27, 9 23°5; hind wing, 5 9, 14-15 mm. 
Hab. Mexico, Santiago Iscuintla, Jalisco (Schumann: 2 3), Tlacotalpam, Vera Cruz 
(Barrett, coll. P. P. C.: 13), Teapa (H. H. Smith: 19); Panama (M. C. Z.: 
1 ¢). 
The males were taken in July, the Teapa female in January. 
As the appendages of the males, the genital valvules of the female, and all other 
structural details appear to be identical with those of L. vacillans, I do not consider 
this form to be of specific rank. There is no vulvar spine on the Panama female, 
which, of the two individuals of this sex, alone possesses the abdomen. 
I would be disposed to regard these five individuals as aged L. vacillans, were it 
not for the fact that the Santiago males appear to be quite young and yet nevertheless 
possess the black thoracic stripes. 
[AMPHIAGRION. 
Amphiagrion, Selys, Bull. Acad. Belg. (2) xli. p. 284 (1876) ; Kirby, Cat. Odon. p. 143 (1890). 
The removal of Agrion heterodoxum and A. flavescens to the new genus Hesperagrion 
(anted, p. 103), leaves in Amphiagrion only two species—A. sauciwm, Burm., and 
A. amphion, Selys. The latter, described from a single female from “ North America,” 
is unknown to me. 
1. Amphiagrion saucium. 
Agrion saucium, Burmeister, Handb. Ent. ii. p. 819 (1889) * ; Hagen, Syn. Neur. N. Am. p. 85 
(1861) °; Calvert, Trans. Am. Ent. Soc. xxv. p. 39 (1898) °. 
Amphiagrion saucium, Selys, Bull. Acad. Belg. (2) xl. p. 285 (1876) *; Calvert, Trans. Am. Ent. 
Soc. xx. p. 235 (1893) °; Kellicott, Odon. Ohio, p. 31 (1899)°; Williamson, 24th Rep. Geol. 
Indiana, p. 267 (1900)"; Ent. News, xi. p. 454 (1900) °. 
Agrion discolor (pars), Burmeister, Handb. Ent. ii. p. 819 (1839) °; Selys, in Sagra’s Hist. Cuba, 
Ins. p. 467 (1857) °; Hag. Syn. Neur. N. Am. p. 79 (1861) “; Calvert, Trans. Am. Ent. 
Soc. xxv. p. 88 (1898) ”. 
Pyrrhosoma abbreviatum, Selys, Bull. Acad. Belg. (2) xli. p. 1299 (1876) ™. 
Hab. Nortu AMERICA, Quebec to South Carolina, west to Montana and Colorado 1-5 ; 
Victoria, British Columbia (2. Osburn, in litt.), Washington °, Idaho [1 ¢ ], Ogden, 
Utah [C. Thomas: 1 3], Reno, Nevada [Morrison 1878: 1 3,12]. (M. C. Z); 
BIOL. CENTR.-AMER., Neuropt., December 1902. r 
