92 NEUROPTERA. 
The individuals from Cafias Gordas were taken in March and seem to belong to the 
same species; I have consequently concluded that the female described as A. variabilis 
by Selys! is of another species, possibly (judging from a female agreeing with his 
description) an aberrant A. extranea. Almost identical in colours and in structure 
of appendages and of mesostigmal lamine are two males from Cauca, Colombia 
(Staudinger, M. C. Z.\, which are somewhat larger—abdomen 30, hind wing 23 mm.,— 
and still larger individuals, a male from San Gerénimo and two females from Zapote, 
Guatemala (Champion). ‘These last measure—abdomen, ¢ 33, 2 28°5; hind wing, 
3 9, 25 mm., and they show only the following slight colour-differences: segment 10 
is blue above in the male, and in the female 5 and 6 are coloured like 38 and 4. ‘The 
appendages of the males of A. variabilis from Guatemala and Costa Rica and of the 
above-mentioned males from Cauca and San Gerénimo are practically identical in form, 
agreeing closely with Hagen’s drawing of those of A. medullaris, Hagen *, and with 
our fig. 538, Tab. IV., of the appendages of the type male of A, variabilis from Vera 
Cruz, when allowance is made for the circumstance that in this last the superior 
appendage is extended rather farther backward than usual. In view of these facts I 
am tempted to unite A. variabilis and A. medullaris, were it not that the description 
of the latter male states that segment 7 is black, with a basal blue ring. It is possible 
that these colours may be due to post-mortem discoloration ; and if so, the only apparent 
objection to the union of these two species would be removed. 
29. Argia rhoadsi, sp. n. (Tab. IV. figg. 55, 55s.) 
3. Rear of the head pale. Pale (blue) antehumeral stripe equal in width to the dark mid-dorsal, Humeral 
stripe with some traces of being forked in its upper half, at its middle one-half as wide as the pale ante- 
humeral. Segment 2 blue, each side with a superior black stripe, dilated before the apex, which it does 
not reach nor unite with its fellow of the opposite side; 3-7 black, with a metallic-green reflection on 
dorsum, with a transverse, basal, blue ring prolonged on mid-dorsum of 3-5 as a narrow stripe or line for 
five-sixths the length of those segments ; 8-10 blue, unspotted. 
Pterostigma of the front wings ‘82 mm. long, of the hind wings ‘94 mm. long, surmounting one cell on one side 
of the body and less than one cell on the other side. 
Antenodal cells on the front wings 4, on the hind wings 3. 
Dimensions.—Abdomen 28°5, hind wing 21 mm. 
© unknown. 
Hab. Mexico, Monterey in Nuevo Leon (fhoads: 1 ¢ ). 
The wings of the unique type, taken April 25, 1899, are pale yellow throughout. 
30. Argia extranea. (Tab. IV. figg. 3, 4, 56, 56s, 56%, 56 i.) 
Agrion extraneum, Hagen, Syn. Neur. N. Am. p. 92 (1861) ’. 
Argia extranea, Selys, Bull. Acad. Belg. (2) xx. p. 399 (1865) ”; Calvert, Proc. Calif. Acad. Sci. 
(3), Zool. i. p. 380, t. 25. fig. 8 (apps. ¢) (1899) *. 
* Bull. Acad. Belg. (2) xx. p. 412 (1865), from Bogota. 
