MICRATHYRIA, 229 
septima prove to be, for the most part, that form of didyma which I have called 
hypodidyma in the footnote to page 224. 
8. Micrathyria debilis, (Tab. IX. figg. 25-27.) 
Dythemis debilis, Hagen, Syn. Neur. N. Amer. p. 168 (1861)*; Proc. Bost. Soc. Nat. Hist. xi. 
p. 293 (1867) *. 
Macrothemis debilis, Kirby, Cat. Odon. p. 33 (1890) *. 
In 1897 I noted from Hagen’s (male) type from Cuba that the two post-triangular rows of the front wing 
extended to beyond the level of the nodus, anterior lamina less prominent than the other parts; hamule 
bifid at tip, inner branch more slender, curved, tip acute, outer branch longer, much wider, tip obliquely 
truncated outward (laterad) and downward (ventrad). Genital lobe about equally prominent as the outer 
hamular branch, rounded at tip. Abdomen 16, hind wing 18, pterostigma 1°75 mm, The remainder 
of my notes agree with what has been given in the synopsis on page 223, 
The present material differs from the type by a greater number of cross-veins as follows :—Front wings, 
8 (rarely 7 or 9) ante-, 5-7 (most frequently 6) postcubitals, instead of 6 and 4 respectively '. The hind 
wings have 6 (rarely 5) ante- and 5-8 (usually 6) postcubitals. The pale marks on segments 3-6 are 
usually at least one-third as wide as the half of the dorsum on which they lie, instead of being mere 
lines on 5-61. The pterostigma, front wing, is 2 mm. long in most of these males and in the Lumija 
and in at least one of the Altamira females, but in the great majority from this last locality it is 2°5 mm. 
The colour-pattern of the sides of the thorax in the females includes a brown stripe on the obsolete first 
lateral suture, forked in its upper half, and a brown metepimeral stripe; the males are too old or 
otherwise obscured to show the colouring of this part distinctly. 
_ Hab. Mexico, Altamira in 'lamaulipas [13 @ ], San Luis Potosi [1 2 ] (Hoag, colls. 
A. N.8., P. P. C.), Frontera in Tabasco [1 ¢ ], Lumija in Chiapas [1 ¢,1 2 ] (coll. 
Westcott) ; Guatema.a, Puerto Barrios (Line, O. 8S. U.: 23 ).—West Inpins, Cuba ! 2. 
Taken in March (Puerto Barrios), June (Altamira), July (Altamira, Frontera, Lumija), 
and September (San Luis Potosi). 
Owing to the differences above noted I was at first doubtful whether these specimens 
should be referred to debilis. Dr. Ris has kindly examined a male from Puerto Barrios 
and a female from Altamira, and writes (25. x. and 6. xi. 1905) :—*“ Your [Puerto 
Barrios specimen]... . is indeed what I have, when working at the de Selys collection, 
considered as WZ. debilis. It is true that no specimens with Hagenian label are in the 
collection, but I found the description agreeing well with the specimens. All of them 
(6 males, 9 females) are from Cuba. Varieties in reticulation are numerous; I have 
noted the absence of the last uncomplete antecubital in 7 wings (twice symmetrical) ; 
absence of the ‘ Antenodalbriickenquerader’ in 8 wings (twice symmetrical, but in 
fore wings only) *. On the number of antecubitals I have no general note, but for 
3 specimens the indications 6, 6, 63 . . .. my description [of the genitalia of the second 
segment ¢]....and a rough pen-sketch agree perfectly with your specimen, and, 
I think, with Hagen’s description as well.” ‘About the female... . I agree with 
you that it is of the species considered as debilis in my notes.” 
* In contrast to these variations, all of the 4 ¢ , 15 9 from Mexico and Central America have two bridge-cross- 
veins on all the wings, and on only one fore wing is the last incomplete (7. e. not continuous) antecubital absent, 
BIOL. CENTR.-AMER., Neuropt., August 1906. Dh 
