120 NEUROPTERA. 
LEPTOBASIS. 
Leptobasis, Selys, Bull. Acad. Belg. (2) xliii. pp. 98, 99 (1877)*; Kirby, Cat. Odon. p. 156 
(1890) *. 
The genus Leptobasis, as established by de Selys!, belongs to a group having, as one 
of its chief characters, “onglets & dent inférieure nulle ou oblitérée”—the tarsal claws 
without an inferior tooth. In the apparent absence of any earlier determination, 
Mr. Kirby? has fixed Z. vacillans, Selys, as the type of the genus. But I find that 
L. vacillans possesses the inferior tooth of the tarsal claws, which, although small, is 
relatively as well developed as in Ceratura, placed by de Selys in the denticulate group 
(cf. figg. 25 and 26, Tab. V.). The second species (L. macrogasira, Selys), included under 
Leptobasis by de Selys, although with doubt, has also been shown to possess denticulate 
tarsal claws, and has been referred to Telebasis (Erythragrion) by Mr. Carpenter. Of 
the five remaining species described by de Selys, I have seen only a single specimen of 
L. diceras, Selys, badly damaged as regards the legs, so that I cannot form an opinion 
as to their status. 
1. Leptobasis vacillans. (Tab. V. figg. 22-25.) 
Leptobasis vacillans, Selys, Bull. Acad. Belg. (2) xliii. p. 101 (1877) *; Kolbe, Arch. f. Naturg. liv. 
1, p. 172 (1888) *. 
$. The brief description? of the appendages leads me to think that these structures were retracted in the 
types so as not to be clearly seen, wherefore the following may be added :—Superiors, viewed from above, 
wider than long with a small tooth on the inner margin, whence the appendage is obliquely truncated 
outward and backward, the outer angle being thus the more acute; in profile, each appendage is bent 
downward at right angles at the apex, the descending part terminating in a minute forwardly directed 
point. Inferiors pale yellow, slightly longer (not “& peine plus courts”) than the superiors, inclined 
toward each other, tapering from base to apex, more especially in profile view, and ending in a minute 
black point which is turned upward and inward. 
Q. Hind margin of the prothorax less produced mid-dorsally than in the g. 
Dimensions.—Abdomen, ¢ 27°5-29°5, 9 25-28; hind wing, ¢ 15, 9 15-17 mm. 
Hab. Mexico, Presidio de Mazatlan (Forrer: 1 9), Atoyac (H. H. Smith: 1 2), 
Temax, N. Yucatan (Gawmer: 23, 1 2), Teapa (H. H. Smith: 93, 92); 
GuaTeMaLA, El Reposo [1 ¢ ], Paraiso [1 ¢ ] (Champion)—West InpDiEs, Cuba ' (Poey, 
1866, UC. Z.: 1 ¢,1 2), Puerto Rico (Moritz ?). 
Taken at Teapa, January, February, and March, at Atoyacin April. I can find no 
differences between the Cuban individuals and those from the continent. 
The “genre Telebasis”” of de Selys (. ¢. p. 97), of which Leptobasis forms the first 
* sous-genre,” is stated to have no vulvar spine in the females. For ZL. vacillans he 
describes} ‘une sorte de petit crochet courbé, court, analogue peut-étre a l’épine des 
Acanthagrion,’ but adds “Le 8 segment de la femelle en dessous a besoin d’étre 
mieux examiné.” The vulvar spine is present in the majority of the specimens before 
me (69-2 °/,; 15°4°/, have lost this part of the abdomen), including the Cuban female. 
I see no reason for doubting that it is the same structure as is present in Acanthagrion 
and Enallagma., 
