In the female _Phyllium_ the hind wings are not present, being represented by a minute process (Fig. 156, B). The tegmen of the female _Phyllium_ is, from various points of view, a remarkable and exceptional structure. It is the rule that when there is in Insects a difference between the alar organs of the two sexes it is the male that has them largest; this is the case in _Phyllium_ so far as the hind wings are concerned, but in the fore-wings the rule is departed from, the leaf-like tegmina of the female being very much larger than the rudimentary wing-covers of the male. In Phasmidae it is the rule that the tegmina are atrophied, even when the hind wings are largely developed. This is the case in the male of _Phyllium_, but in the female this normal condition is reversed. Although the alar organs of Phasmidae have received hitherto but a small amount of attention, it is probable that the female tegmen of _Phyllium_ is as peculiar morphologically as it is in other respects. In Fig. 156 we give an accurate representation of the chief nervures in the tegmen of a female _P. crurifolium_. It is interesting to compare this with the diagrams we give of the tegmina of a Blattid (Fig. 121) and of an Acridiid {270}(Fig. 167); the tegmen of the _Phyllium_ is very different, the radial vein and all the parts behind it being placed quite close to the posterior edge of the structure. A similar view is taken by both Redtenbacher and Brauer. The latter says,[198] "In _Phyllium_ (the walking-leaf) almost the whole of the front wing is formed by the praecostal and subcostal fields; all the other fields with their nervures, including even the costa, are compressed towards the hind margin into a slender stripe. In the hind wing the costa is, however, marginal." Unfortunately no examination appears to have been made of the male tegmen, so that we do not know whether that of the female differs from it morphologically as strongly as it does anatomically. It is, however, clear that the tegmina of the female _Phyllium_ not only violate a rule that is almost universal in the Insecta, but also depart widely from the same parts of its mate, and are totally different—and, for a Phasmid, in an almost if not quite unique fashion—from the other pair of alar organs of its own body. [Illustration: FIG. 157.—Egg of _Phyllium scythe_. (After Murray.) A, The whole egg, natural size; A', magnified; B, the capsule broken, showing the true egg inside, natural size; B', magnified.] {271}[Illustration: FIG. 158.—Portion of a longitudinal section of the egg capsule of _Phyllium crurifolium_: _a_, external; _b_, middle; _c_, inner zones; _d_, elongate alveoli. × 100. (After Henneguy.)]