232 Mr. R. Shelford’s Studies of the Blattide. 
seen by the foregoing that the Ectobiinze and Phyllodromiinee 
possess features common to both sub-families, and the 
question arises as to whether there does exist a character 
that can be relied on as a diagnostic criterion of sub-family 
rank. I own to having been nearly completely baffled in my 
search for such a character, and I have seriously considered 
the advisability of transferring the genera Hetobia and 
Hololampra (= Aphlebia) to the Phyllodromiine, leaving 
in the depauperated Ectobiinzee—henceforth to be called, 
following de Saussure, the Anaplectinze—only the genus 
Anaplecta and a new genus described below. 
However, it is not necessary to make such a revolutionary 
change, for I believe that I have hit on a feature of great 
use in distinguishing the members of the two sub-families 
in question, namely, the form of the vena ulnaris of the 
wing. This vein is either simple or bifurcated or else 
ramose, and it is to be noted that when this vein is ramose 
a reduction in size of the triangular apical field generally 
ensues, the reduction leading on in many cases to entire 
obliteration. Moreover it is possible to trace a shifting 
backwards of the apical triangle ; in Hetobia lapponica, L., 
this field is close to the anterior margin of the wing so that 
the median vein and ulnar vein impinge on its upper 
border, and do not attain the outer margin of the wing; 
in such a species as Theganopteryx conspersa, Sss., the apical 
triangle is shifted back so that the median vein and the 
upper branch of the bifurcated ulnar vein reach the outer 
margin of the wing, anterior to the apical triangle and 
only the lower branch of the ulnar vein impinges on it; in 
many species of Phyllodromia the median vein and the 
numerous branches of a ramose ulnar vein all reach the 
outer margin of the wing, the apical triangle having 
undergone a further backward shifting; finally we have 
those forms, such as the species of Pscudomops in which 
the apical triangle has disappeared entirely, and in these 
the anterior part of the wing projects beyond the posterior 
part, producing a marked sinuosity of the outer margin. 
Taking into consideration the great range of variation of 
these characters, T find it not possible to use them as criteria 
of sub-family rank, except to this extent, that all forms 
with a single or bifurcate ulnar vein and a conspicuous 
triangular ‘apical field may be regarded as Ectobiinz, and 
those forms with ramose ulnar vein as Phyllodromiine, 
whether the apical triangle is present reduced or absent. 
