PALEMNEMA. 135 
I have used the male-appendages to separate these species in conjunction with the 
presence or absence of dark brown on the wing-tips, because the material before me 
seems to negative the specific distinctions employed by de Selys, such as the point of 
termination of the superior sector of the triangle, the size of the pterostigma and the 
number of cells it surmounts, the coloration of the prothorax, the point of origin of 
the nodal sector, &c. At the same time it should be pointed out that I have, in most 
species, only a single male with the appendages present. If future material should 
prove these organs not to be constant in their shapes, P. angelina, P. nathalia, and 
P. domina, not to mention others, will apparently have to be considered as forming a 
single species. As to the females, I have grouped them chiefly by size and locality 
with corresponding males, as I can find no other characters. 
1. Palemnema desiderata. (Tab. V. fig. 39.) 
Palemnema desiderata, Selys, Mem. Couron. Acad. Belg. xxxviii. p. 146 (1886) *. 
? Palemnema paulina (nec Drury), Selys, Bull. Acad. Belg. (2) x. p. 434 (1860) ?; Mem. Couron. 
Acad. Belg. xxxviii. p. 146 (1886) *. 
The Presidio male, taken in July, is the only individual I have seen; it agrees better with the description ? of 
P. paulina, Selys, than with that of P. desiderata*, but has the sides of the thorax blue instead of yellow; 
a small superior tooth on the superior appendages at one-fourth their length, not mentioned in any 
account cited above (see Tab. V. fig. 39); superior sector of the triangle ending 6 cells beyond the level 
of origin of the ultra-nodal sector on the front wings, 9 on the hind; pterostigma on the front wing 
surmounting 4-5 cells, its costal edge measuring 1-4 mm. long; postcubitals 28-29 on front wings, 25-26 
on hind; abdomen 44 mm., hind wing 31 mm. 
Hab. Muxico ' (Ghiesbreght?), Presidio in Vera Cruz (Barrett, coll. P. P.C.: 1 ¢). 
The description! of P. desiderata is purely comparative; de Selys himself said of 
this form that it “n’est probablement qu'une race, peut-étre méme une variété 
individuelle” of his P. paulina. Judging from the other material of this genus which 
I have studied, I incline to the opinion that the characters he employed to separate 
P. desiderata are not of specific, or even varietal, value. If it should hereafter be 
proved that P. desiderata, Selys, and P. paulina, Selys, are distinct, the latter will 
require a new name, owing to the change introduced under the following species. 
as P. helena, from Bogota, also offer some interesting comparisons with Palemnema, but here again there are 
notable differences, as in the points of origin of the lower sector of the triangle and the position of the normal 
submedian cross-vein. , 
These comparisons of Palamnema with genera of the legion Podagrion have been suggested not only by the 
above-quoted remark of de Selys but also by another of his:—“ Par sa réticulution incomplete elle [i. e. the 
genus Hemtphlebia | peut-étre considérée comme la derniére parmi les Agrionines 4 quadrilatére en trapéze (Légions 
Lestes et Agrion), comme les Protoneura sont les derniers sous un rapport analogue parmi les Agrionines & 
quadrilatére régulier (Légions Pseudostigma—Podagrion—et Platycnemis). Ce n’est, en effet, qu’en deux 
séries paralléles que l'on peut classer convenablement les Agrionines et non en une ligne continue” [Bull. 
Acad. Belg. (2) xliii. p. 158 (1877)]. The italics are mine, but I may add that, after all, the distinction based 
on the shape of the quadrilateral may not prove to be so important as it has been considered to be. 
