198 NEUROPTERA. 
Cordulines (sensu Selysii) au Mexico ou dans |’Amérique centrale, je crois qu'il n’en 
existe dans ces pays aucune espéce. Peut-étre, une ou deux espéces de Macromia qui 
ont été observés au Texas ou en Californie pourront-elles se trouver au Mexique, mais 
ce n’est méme pas certain. Je n’ai aucune connaissance de Corduline dépassant, au 
Nord, le Texas et la Californie, et dépassant, au Sud, Ecuador et le Pérou.” 
Subfam. LIBELLULINA. 
Synopsis of the Mexican and Central- American Genera. 
A. Hind lobe of prothorax having its upwardly and backwardly projecting 
middle portion narrower than the middle lobe, the hind margin of this 
middle portion entire in most of the genera. 
B. Sectors of the arculus on the front wings arising not from a common 
stalk, or from a common stalk not as long as the lower piece of the 
arculus; sectors of the triangle on the hind wings arising from the 
same point. 
C. Nodal sector waved in its middle, discoidal and internal triangles of 
the front wings cross-veined, eyes in contact for a distance less than 
the mid-dorsal length of the occiput, subnodal sector and supple- 
mentary sector next below separated from each other by at least 
two rows of cells, proximal side of the triangle on the hind wings in 
prolongation of the arculus or nearly so. 
D. Bridge-cross-veins * two or more (one subnodal, the others ante- 
or post-nodal), vulvar lamina of female not projecting at right 
angles from the abdomen. 
E. Males with a projecting ventral plate on abdominal segment 1 
more or less deeply divided into two branches; females with 
the third tibiz not longer than the third femora . . . . . Puaruemisf. 
EE. Males with no ventral plate on abdominal segment 1; females 
with the third tibie a little longer than the third femora . . Lispeniuna. 
DD. Bridge-cross-veins one (subnodal), vulvar lamina of female 
projecting at right angles to the abdomen, hind wing with the 
discoidal triangle cross-veined, front wing with the last ante- 
nodal not continued to the median vein . . . . . . . . « PSEUDOLEON. 
* Attention was first called to these cross-veins by Dr. F. Ris (Mitth. schweiz. ent. Gessell. x. p. 440; 
Ent. News, xiv. p. 218, 1903). My statistics show that their number is a much more constant generic 
character, in American forms at least, than Prof. Foerster’s remark (Ann. Mus. Nat. Hung. 1903, p. 512, 
footnote) would imply. 
+ Differs from the Palearctic Platetrum depressum in having usually, on the hind wings, the discoidal 
triangle 2-celled instead of 3- or more-celled, one instead of two submedian cross-veins, no supratriangular 
cross-veins ; on all the wings, two rows of cells instead of one between the short sector and the supplementary 
sector next below ; sides of abdominal segment 8 of the female perfoliate. 
