ORTHOPTERA 



FAM. BLATTID^ 



SUBFAM. BLATTIN^ (= PERIPLANETIN^) 

 by R. SHELFORD 



WITH 2 COLOURED PLATES 



^'^^■^HE Blattinae (Periplanetinie) form the fourth subfamily of the Blattidse. 



, f^^ Characters. — Antennae setaceous and usually much longer than the body, very 



rarely plumose or incrassated. Head with the vertex usually exposed. Eyes reniform. 

 Ocelliform spots rareh" absent. Tegmina and wings completely developed, reduced, 

 rudimentary nr absent; when present usually semicuriaceous; the costal veins of the wings irregular 

 and much blanched, ulnar vein of the wings multiramose, the branches irregular and bifurcated. 

 Sub-genital lamina of male typically quadrate and sj-mmetrical with a pair of slender genital styles. 

 Sub-genital lamina of female modified to form a pair of apposed valves. Cerci variable, but generally 

 flattened and acuminate. Femora generally strongly spined beneath. Tarsi variable. Ootheca chitinous, 

 carried with the suture uppermost. None of the sf>ecies viviparous. 



This is a very well-defined subfamily on account of the valvular structure of the female sub-genital 

 lamina, whilst the males can also be readdy distinguished by the symmetry of the sub-genital lamina 

 and by the slender but well-marked styles. 1 have met with no forms that can be regarded as intermediate 

 between this and other subfamilies of Blattidse. I cannot follow Bolivar in maintaining the subfamily 

 Nocticolinae for the cavernicolous genera Nocticola and Spelaeoblatta ; to my mind the undoubted Blattine 

 features of the female sub-genital lamina in these genera over-ride in importance characters that have 

 been called into existence by the cave-haunting habit. Sexual dimorphism is a very marked feature ot 

 the I'.lattina£ and some confusion has resulted from its non-recognition by some authors; there is no 

 doubt that the number of known sjiecies of Deropeltis and Pseudoderopeltis will be reduced \\ hen we gain 

 more exact knowledge of the two sexes of both genera ; several species oi Pseudoderopeltis, described from 

 females alone, have been placed in Stylopyga b}' older authors, so that the synonym}^ is somewhat 



