Fig. 134.—Front leg of Periplaneta australasiae.
The classification of the Blattidae is attended with considerable difficulty on account of the numerous wingless forms, and of the extreme difference in the organisation of the two sexes of many species. It has, however, been brought to a fairly satisfactory state by the reiterated labours of Brunner von Wattenwyl, and we reproduce his recently perfected exposition of their characters. His first division is made by means of a structure which is very easily observed, viz. whether the femora are armed with spines, as in Fig. 134, or not. The terms used in connexion with the wings and other parts of the body we have already explained.
Brunner's system is adopted by de Saussure,[[168]] who, however, proposes to replace the names Ectobiides and Oxyhaloides by Anaplectinae and Plectopterinae. He also proposes to apply the generic name Blatta to the Insect that is now so frequently called Phyllodromia germanica in zoological works. If that view be adopted, Brunner's group Phyllodromiides will be called Blattides.
Table of the tribes of Blattidae, after Brunner:—
1. Femora spiny beneath.[[169]]
2. The last ventral plate of the female large, without valves.
3. Supra-anal lamina of both male and female transverse, narrow. Wings, when present, furnished with a triangular apical field. Posterior femora unarmed beneath, or armed with two spines on the anterior margin. Egg-capsules furnished with a longitudinal suture. Tribe 1. Ectobiides. [Anaplectinae Saussure.]
3′. Supra-anal lamina of each sex more or less produced, triangular, or emarginate. Wings, when present, without apical field. Posterior femora with both edges spiny.
4. Supra-anal lamina of each sex triangular, not notched. Cerci projecting much beyond this lamina.