196 
[October 
The Brd division of the 1st or sexual Synoptical Table (p. 367) must 
also be slightly amended, and read as follows:— 
f Legs all short; (interme¬ 
diate seta short % , sub- 
Eyes % not contiguous, equal 9 •) 
simple; (intermediate 
setf),, when present, Legs &g. 
subequal, short, or ru- 
dimental.) 
Legs &c. 
1 
Palixgenia, subgenus A 
{=Pentagenia, n. g.) 
Palixgexta, suhgenus B 
{=IIexagenia, ii. g.) 
Palixgenia, subgenus C 
{=IIeptagenia, n. g.) 
While on this subject I may add, that in both the sexual and the 
non-sexual tables, in the 1 st primary dichotomous division, instead of 
“costal cross-veins numerous, robust, regular,” we should read “costal 
cross-veins distinct and plain on the middle of the costa”; and in the 
2 d dichotomous division, instead of “ partially absent ” or “ entirely 
absent on some part of the costa,” read “ entirely absent in the middle 
of the costa.” In Hept. maculipennis n. sp., the costal cross-veins are 
not “ regular,” but arranged in groups, and in Bsetis suhgenus C. they 
are entirely deficient, except the oblique vein next to the body, on the 
basal i of the costa. In Hept. simplex again they are deficient, with 
the same exception, on the basal 1 of the costa. Thus does Nature, 
even fruitful and abundant, mock the lagging labors of systematists! 
In proposing the above three genera, I have followed Dr. Hagen’s 
example, who has given the same termination to a number of new 
genera of Libellulina, founded by him, (Celithemis, Plathemis, Lep- 
themis, Dythemis, Erythemis, Mesothemis, and Perithemis,) which is 
a great assistance to the memory in determining the position of those 
genera in a systematic arrangement. The new genera may be thus 
characterized:— 
Pentagenia n. g. Wrings four, hind wings wide, all with nume¬ 
rous cross-veins; costal cross-veins in the front wing numerous, never 
absent in the middle of the costa. First tarsal joint distinct in the 
anterior legs S 9 5 indistinct and connate in the four posterior legs 
S 9 , in all the legs shorter than the 2 nd tarsal joint; anterior tibiaS 
much longer than the femur; ant. % legs not much longer than ant, 
9 legs; all six legsS 9 short, the hind legs not nearly attaining the tip 
of the abdomen. Intermediate seta short % , scarcely half the diameter 
of the other two; nearly as long as the others in 9 and only slightly 
less robust; all the three setae % 9 glabrous. Eyes % separated by a 
