of ' Fossorial Hymenoptera. 57 



shining ; thorax opaque. Head : mandibles ferruginous, with 

 their base black ; the anterior margin of the clypeus rounded ; 

 the head behind covered with silvery pile, a patch of the same on 

 each side of the clypeus. The thorax covered with a changeable 

 silvery pile, most sparingly so on the mesothorax ; the legs 

 pilose ; the scutellum shining ; a patch of bright silvery hair 

 on the metathorax close to the insertion of the posterior coxeb ; 

 wings dark brown, and having a coppery and violet iridescence 

 in certain lights ; the base of the posterior pair subhyaline. 

 Abdomen smooth, shining, and impunctate. 

 Hab. Ega ; St. Paulo. 



Larrada limpidipennis. 



Female. Length 5^ lines. Black, with pale flavo-hyaline 

 wings ; their tegulae and all the nervures towards the base of 

 the wings bright yellow, but towards their apex becoming 

 slightly darker; a faint cloud at the apex of the superior 

 pair. Head : the clypeus densely covered with bright silvery 

 pile, the cheeks also pilose ; the mandibles, and the antennae 

 beneath, ferruginous. The metathorax, the coxae, and femora 

 beneath, covered with bright, changeable, silvery pile ; the 

 apical joints of the tarsi ferruginous. The apical margins of 

 the three basal segments of the abdomen with fasciae of bright 

 silvery pile. 



Hab. Para. 



Genus Tachytes, Panz. 

 Tachytes iridipennis. 



Female. Length 3-3f lines. Black ; wings hyaline, and 

 exhibiting beautiful iridescent colours in different lights. 

 Head : the lower part of the face and the clypeus covered with 

 bright silvery pubescence. The mesothorax shining and finely 

 punctured ; the metathorax above with longitudinal, fine, 

 divergent striae ; the wings with the neuration black and the 

 tegulae pale testaceous ; the apical joints of the tarsi ferruginous ; 

 the sides of the thorax beneath, and also the legs, with a thin, 

 changeable, cinereous pilosity. Abdomen conical, very thinly 

 pilose, shining, and with changeable silvery fasciae on the apical 

 margins of the segments ; beneath smooth and shining. 



Hab. Ega. 



Tachytes fervens. 



Male. Length 4| lines. Black ; the legs ferruginous ; 

 adorned with golden pubescence. Head : the face and clypeus 

 covered with bright golden pubescence ; the mandibles fer- 



