232 Mr. R. Slielford's Studies of the BlattidcV. 



seen by the foregoing that the Ectobiinse andPhyllodromiiuse 

 possess features common to both sub-famiHes, 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 Edohia and 

 llololamiwa (^ = Aplddyia) to the Phyllodromiinse, leaving 

 in the depauperated Ectobiina? — henceforth to be called, 

 following de Saussure, the Anaplectioce — only the genus 

 Anaplccta and a new genus described below. 



However, it is not necessary to make such a revolutionary 

 chauoe, 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 Uctohia lapiJonica, 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 Thcganoptcrf/vecmsjyersa, 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 VkiiUodromia 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 Pseitdomoj^s 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, I 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 Ectobiinfe, and 

 those forms with ramose ulnar vein as Phyllodromiina3, 

 whether the apical triangle is present reduced or absent. 



