[ 249 XXIV. Descriptions of the Nests of two Hymenopterous Insects inhabiting Brazil, and of the Species by which they were constructed. By John Curtis, Esq., F.L.S. 8^c. &;c. Read February 6th, 1844. Of the various departments in natural history which engage the attention of man, none are more interesting or more calculated to elevate his mind and to furnish him with a pure and endless source of amusement than the economy of insects. Every one who supplies any data bearing upon this subject contributes in no small degree to the advancement of natural history by augmenting the store of materials upon which true science and philosophy are based. It is the record of facts which has rendered the works of Reau-mur and De Geer so interesting and invaluable. If we look to those insects which furnish the greatest variety, sagacity, and even design in their economy, the orders of Hymenoptera and Lepidoptera will perhaps be the most highly estimated. This, however, is a subject which I will not enlarge upon here ; but I am happy in the opportunity of making known to the Linnean Society two insects, whose nests are highly interest-ing, the one being a structure of nidus perfectly novel in the family to which the insect belongs ; and the other, although similar to that of a congenerous species, differing from those which had been previously described. For these materials I am indebted to my esteemed friend Lord Goderich, to whom they were presented, with many other curious insects, by the Right Honourable Henry Ellis on his return from a special mission to Brazil. On looking over this collection, I saw two insects which were stated to be the two sexes, taken from a nest in an accompanying box, in which also I found a female fly : these I will forthwith describe, and afterwards enter upon the history of this remarkable animal. It is of the Ord. Hymenoptera, Fam. Tenthredinid^, and Gen. Hylotoma oi Klug:
BioStor
