This species, of which a single male of the forma maxima is before us, although very closely allied to P. cavifrons Hope ¹) from the Philippines and to P. patricius Schauf. from Celebes, might be at once separated from both by the front-margin of the head, being without the crestlike elevation which in the above cited allied species is already quite obvious in specimens of median development; moreover the dentition of the mandibles is different. The mandibles of javanensis are longer than the head and thorax taken together, flattened, very slightly incurved for about the basal three fifth of their length, almost straight for the following fifth, thence gently bent inwards in an oblique direction; armed with a very large blunt dentiform process at the base, a large obtuse tooth somewhat higher up, a series of five small blunt contiguous teeth along the straight portion at four fifth of their length, and finally a rather large tooth at some distance from the pointed tip, forming with the latter a terminal fork.