COLLECTED AT CELEBES. 85 



apical segments black ; the palpi white. The sinus of the eyes, cly- 

 peus, and cheeks, clothed with silvery pubescence ; a deep channel 

 runs from the anterior ocellus to the base of the clypeus ; the front 

 very convex on each side of it. The thorax beneath, as well as the 

 sides, with silvery pubescence ; the raetathorax with a central longitu- 

 dinal impressed hne, extending from the base to the apex ; the wings 

 hyaline and iridescent, the nervures dark fuscous. 



Hab. Makassar. 



Although the differences which separate this and the two preceding 

 species are apparently slight, still they are, in my opinion, of full 

 specific value; T.ferox is distinguished from T. elegantulum by the 

 deeply impressed line down the centre of the metathorax, and by the 

 dark nervures and stigma of the wings, and the latter may be at 

 once known from T. gracilescens by the deep channel down the centre 

 of the metathorax, and by its longer and black petiole. 



4. Trypoxylon gracilescens. T. nigrum, laeve, nitidum; an- 

 tennis pedibusque pallide ferrugineis ; abdomine ferrugineo, petiolo 

 nigro. 



Female. Length 6^ lines. Head, thorax, and petiole of the abdomen, 

 shining black ; the antennae, anterior margin of the clypeus, mandi- 

 bles, and legs pale ferruginous ; abdomen, except the petiole, ferru- 

 ginous. The face and clypeus, the sinus of the eyes, and the cheeks, 

 covered with silvery pubescence. The posterior margin of the pro- 

 thorax nairowly pale testaceous and fringed with short silvery hairs ; 

 the sides of the metathorax and the pectus silvery ; the metathorax 

 with a deeply impressed central longitudinal line extending from the 

 base to the apex; wings hyaline and iridescent, the nervures and 

 tegulse pale rufo-testaceous. 



Hab. Makassar. 



G-en. PsEN, Latr. 



1. PsEN ERRATicus. P. atcr ; pedibus abdomineque ferrugineis, pe- 

 tiolo nigro. 



Female. Length 5 lines. Head, thorax, and petiole of the abdomen 

 black ; the abdomen and legs ferruginous, the latter palest. The head 

 and thorax covered with short silvery-white pubescence ; the mandi- 

 bles and antennae pale ferruginous, the latter fuscous above, becoming 

 black towards the apex ; the scape yellowish in front. The wings 

 hyaline and brilliantly iridescent ; the nervures and stigma pale fer- 

 ruginous ; the coxae fuscous above. Abdomen shining and impunc- 

 tate ; the petiole wider at its extremity than at its base, curved, and 

 very smooth and shining. 



Hab. Makassar. 



The discoveiy of a species of Psen in Celebes is highly interesting; 

 previously only a single species from Brazil had been discovered out 

 of Europe. 



