the Ortlioptera in the British Museum. 153 



Platacanthoides Kirby. 



1870. Plafacanthus Walk., Cat. Derm. Salt. B. M., iv, 

 p. 714, genus 35 (preoccupied by Fischer in 1850 for 

 a genus of fisli). 

 1910. PUiacanthoides Kirby, Syn. Cat. Ortb., iii, p. 559. 



Of middle size, not rugose. Antennae scarcely flattened. Face 

 slightly reclinate. Frontal ridge in profile more or less convex, 

 but only feebly prominent between the antennae, feebly impressed 

 or flat; lateral margins straight, gradually and feebly divergent 

 do\vnwards. Fastigium of the vertex distinctly sloping, not separ- 

 ated from the frontal ridge and forming a widely' rounded angle 

 with it, elongato-hexagonal, or oval, in the females scarcely longer 

 than broad; its surface almost flat, or slightly impressed. Cheeks 

 smooth, with the oblique sulcus feeble. Eyes distinctly higher 

 than long and than the subocular sulcus is high. Pronotum with 

 the disc almost flat, median keel well developed, in profile straight 

 or nearly so, feebly cut by the transverse sulci ; metazona subequal 

 to prozona, or shorter ; its hind angle obtuse, or straight, not at all, 

 or but slightly rounded ; lateral keels low, but distinct, complete, 

 more or less convex, distinctly divergent backwards, reaching the 

 hind margin ; lateral lobes slightly convex, higher than long ; loAver 

 margin rotundato-angulate in the middle. Prosternal tubercle 

 widened towards the apex, which is emarginate, on truncate. 

 Mesosternal interspace in the male slightly, in the female distinctly, 

 transverse. Elytra and wings developed, but in the females not 

 reaching the apex of the abdomen. Hind femora dilated, but 

 scarcely incrassate, vnih. the lower carina regularly convex. Hind 

 tibiae in both sexes straight. 



(J. (The description taken not from the genotype, in which the 

 male is not yet known. ) Last tergite dilated, with a deep and broad, 

 rotundato- quadrangular emargination behind. Supra-anal plate 

 subquadrate with only a pair of chitinous tubercles, Mdth an obtuse 

 median carinula, widely bifurcate in the basal half; hind angles 

 straight; apical lobe small, with two small lateral emarginations 

 at its base. Cerci strongly sinuate, or hook- shaped, with the basal 

 part almost horizontal and dilated inwardly, the apical part vertical. 

 Subgenital plate obtusely conical. 



$. Subgenital plate feebly convex; hind margin with an obtuse 

 triangular projection and two not deep, rounded emarginations. 

 Lower valves of the ovipositor short, obtusely dentate basally. 



Genotype : Plafacanthus morosus Walk. 



The above re-description of this (Walker's) genus is 



