324 . MR. HENRY WALTER BATES ON PHASMIDE. 
He points out that in certain cases where the unwinged female alone was known, the 
author of the Monograph himself confessed he could not decide whether the species be. 
longed to the winged division (i. e. winged in the male) or to the apterous division ; and 
in one instance at least, Lonchodes feruloides, he had placed a species in the apterous 
division, which, now that the winged male was known, proved to bea Phibalosoma of the 
winged division. This implied that winged and wingless species (in the male) might be 
included under one and the same genus; and the critic argued, from the analogy of other 
families of Orthoptera where genera occurred containing both forms (e. g. Saga, Grylla- 
cris, &c.), that the alary structure was an erroneous principle to adopt in the classifica- 
tion of these insects. To the instance brought forward by Gerstaecker I can add several 
others. For instance, Acanthoderus bufo (Westw.), an apterous species, has, except in 
wings, all the essential characters, and especially the elongated anal pseudosegment in 
the female, of the genus Heteropteryx, which is winged in both sexes. In another case, 
the genus Dimorphodes, whose males are winged, a new species has been taken by Mr, 
Wallace in the islands of Batchian and Ternate, very closely allied in the female to West- 
wood's typical species of the genus, but apterous in the male sex. Other less decisive 
. eases might be mentioned. 
A careful examination of the extensive series of Phasmidæ in the Saundersian collec- 
tion has convinced me that the objections thus producible against a classification founded 
on the absence or presence of wings, could be brought forward with equal justice if other. 
organs were taken as the groundwork. The only other classification of the family which 
has been proposed is the one first sketched out by Latreille and developed by Serville, and. 
which takes various other features as guides, especially the armature of the legs. This 
leads to equally artificial results, such as separating widely Bacteria and Bacillus, Phi- | 
balosoma and Bacteria, and so forth. The wording of the objections to the alary system ; 
by the Berlin Professor, as in all such cases, implies that there exist in the nature of the 
thing the materials for a neatly definable classification of the group, which the Mono- 
grapher had failed to discover. But I believe such materials do not in this case exist. In 
other words, I believe that in the Phasmidæ, as in some other groups, Nature, in adapt- | 
ing her species to their conditions of life, has, in the process of variation and adaptation, 
involved all those parts of structure which usually yield, by their partial constancy, d 
racters for the definition of generic groups. The type of structure of the family is, more 
over, as I have before said, homogeneous to an unusual degree, considering the very wide 
range of dissimilarity that it embraces. This explains why apterous species are so closely E 
allied by affinity to winged species, and why, when other parts of structure are taken for 
characters, species are widely sundered which in reality are closely related. The family [ 
is an isolated one in its order, so much so that it is impossible to say what genus in its 
more nearly related to a neighbouring family than any other genus ; and as its type Me 
evidently simple at its origin, and not compounded of two or more allied types which | 
throughout their subsequent modification, have not receded too far to be included in uc 
family, all the existing species are very closely related to each other. It has even beet 
— by writers on the group that the principal great modifications of structure W^ 
do exist, namely those involving the thoracic segments, are due to the development e 
