134 NEUROPTERA. 
half, the widening being gradual, a small acute tooth on the upper surface of 
the superiors at one-fourth their length, a distinct interval between this tooth 
and the widening of the inner margin. Female unknown. . . . lL. desiderata. 
2. Wings of the male with the apical seventh to eighth dark brown, which begins 
at the level of the proximal end, or of the middle, of the pterostigma ; inner 
margin of superior appendages of male distinctly angulate at two-thirds their 
length, where the appendages widen to form the apical third, an acute superior 
tooth on the superiors at one-third their length, with a distinct interval or 
notch between this tooth and the angulation of the inner margin. Female 
unknown. 2. ee ee ee ee ee we ew eR, patulina. 
3. Wings of both sexes without distinct brown markings. 
a, Superior appendages of male as above described for P. paulina . . . . . 3. angelina. 
aa. Superior appendages of male with the inner margin not distinctly angulate 
where the appendages widen to form the apical ¢hird, the widening being 
gradual, a larger acute tooth on the upper surface at one-third their length, 
a distinct interval between this tooth and the widening of the inner 
margin... . . coe eee ~ . 6 « 4 nathalia. 
aaa. Superior appendages of male with the : inner margin not distinctly angulate 
where the appendages widen to form the apical alf, the widening being 
eradual, an obtuse tooth-like projection on the upper surface at almost half 
their length, there being consequently no interval between this tooth and the 
widening of the inner margin when the appendage is viewed from above . 5. domina. 
embrace the following :—The general facies, particularly in the colour-pattern of the wings, which is shown 
in the parallel series of species of the two genera—thus Palemnema desiderata resembles Paraphlebia zoe and 
P. quinta, Palemnema paulina, Drury, nec Selys, is similar to Paraphlebia duodecima, Palemnema angelina and 
P. nathalia to Paraphlebia hyalina (cf. pp. 59-61, 133-134) (this parallelism suggests instances of Lepidopterous 
mimicry, but the needful field observations are lacking); the extent to which the middle lobe of the labium is 
bifid; the length of the biserial hairs on the tibie; the presence of a second or supplementary submedian 
cross-vein ; the superior sector of the triangle reaching to beyond the half of the wings; and the large 
forcipated superior appendages of the males. The differences between the two genera are, on the other hand, 
quite considerable. In addition to those already given (antea, p. 51) as separating their respective legions, 
they include the greater width and rounder tips of the wings of Paraphlebia; the different position of the 
supplementary submedian cross-vein, which in Paraphlebia lies under the quadrilateral beyond its middle; 
the point of origin of the inferior sector of the triangle—at the normal submedian cross-vein, proximal to the 
arculus, in Palemnema, usually at the supplementary submedian cross-vein, distal to the arculus, in Paraphlebia ; 
the normal submedian cross-vein of Paraphlebia is nearer to the first than to the second antecubital; quadri- 
lateral reaching to beyond the level of the nodus in Paraphlebia, not as far as the nodus in Palemnema ; in 
most species of Paraphlebia (see p. 59) the median sector arises at or slightly beyond the vein descending from 
the nodus, the subnodal beyond that vein, while in Palemnema the median sector arises proximal to the vein 
descending from the nodus, the subnodal sector at that vein; the shapes of the pterostigmata and of the 
superior appendages of the males. These differences appear to me to render it unlikely that Palemnema could 
have arisen by reduction of venation from a Paraphlebia-like ancestor. 
There are rather greater resemblances in venation between Palemnema and Heteragrion, but there are also 
such differences as the points of origin of the median and subnodal sectors. The wings of such a Philogenia 
