24 HYMENOPTERA ACULEATA. 



in banks ; many myrmecopLilua beetles associate with it. 

 The walls of its galleries are formed of a substance made of 

 small bundles of woody fibre glued together by a liquid 

 emitted by the mandibular and metathoracic glands, which 

 are peculiarly developed in this species. It swarms in July 

 and August, and gives off a most pungent aromatic smell. 



L. umbratus, Ni)l., (race mixtus, Nyl.). — c? and ? dark 

 chocolate-brown, legs and antennae paler, head as wide as or 

 wider than the thorax ; 5 Aavous ; c? mandibles (vith five 

 teeth ; wings smoky from the base to beyond the middle, 

 their nervures and stigma dark ; abdomen clothed with fine 

 semi erect hairs, scale of the petiole very slightly notched 

 above. 



? much larger than the S , somewhat shining, clothed 

 with fine sheeny pubescence ; mesonotum somewhat 

 flattened, wings very dark at the base ; abdomen not much 

 wider than the thorax, scale slightly notched ; tibiaj with 

 erect hairs. 



5 entirely flavous, clothed with erect hairs, no trace of 

 ocelli, scale of the petiole high, slightly narrowed towards 

 the apex which has a slight notch ; tibiaa with erect hairs. 



L. c? 3-5 mm., ? 7 mm., ? 3-5 mm. 



Race 7>iixta differs from the typical form in having the 

 head rather narrower, and the tibias in the ? and 9 without 

 exserted hairs. Generally distributed but less common than 

 flavus. Nests usually underground, but have been noticed 

 in decaying wood, and the Rev. W. F. White says that this 

 species has been found by him in the stem of a plant of 

 Weifjelia rosea, in which it had carved out its own chambers 

 and corridors. Swarms in August and September. 



L. flavus, De Geer. — S head narrower than the thorax, 

 and the mandibles with only one terminal tooth, forehead 

 without a distinct channel ; wings with the nervures and 

 stigma pale, only very slightly clouded near the base. 



? head narrower than the thorax ; wings slightly clouded 

 at the base; abdomen much wider than the thorax; tibiae 

 without exserted hairs. 



