Isosoma.–So much has been lately written about this genus that it may be dismissed with a few words. The Eurytomidae, to which it belongs, were considered by Nees to be in a debatable state between the chalcidiae and the cynips tribe, and though they are now fixed with the chalcidiae, there is still matter for argument as to their maintenance by animal life, or by vegetable life, or as to how they are divided between these two means of existence.

The former notice of this species was very brief and imperfect, having as there stated, been made from a single specimen which had been untimely nipped from its pupa case. since then I have bred and captured other specimens. It may be G. Venustella Clem., proc. Acad. Nat. Sci., 1860, P. 92,and re-described by Dr. Clemens, Proc. Ent. Soc. Phila, 1863, p. 216. It does not agree accurately with either of Dr. Clemens' descriptions, but it seems to be a somewhat variable species, though some of the most striking marks in my three specimens are not mentioned by Dr. Clemens.

æ.–Sanguineous, shining; head, antennæ, prothorax, surroundings of scutellum, pleura beneath, four anterior legs, including their coxæ, posterior trochanters and their tibiæ and tarsi, black; sides of mesothorax tinged with blackish; metathorax coarsely punctured above with four longitudinal carinæ, the two central ones approximate, flanks less coarsely punctured; wings uniformly fuliginous, with the usual hyaline angular streak beneath stigma; abdomen long, narrow, polished, with a purplish reflection; ovipositor longer than body. Length ·37 inch.

Several years ago, the American Association for the Advancement of Science appointed a committee to reconsider the canons of biological nomenclature, and to report whether, with the growth of science, they requrired any additions or alterations. No report has yet been made, nor, so far as we are aware, is any likely to be presented, until the subject is again brought prominently forrvard and new instructions given. Professor A. E. Verrill has since repubiished the Revised Rules of Zoological Nomenclature adopted by the British Association for the Advancement of science in 1865, and has accompanied them by a few apt comments; in England, Mr. W. F. Kirby, in a paper read before the Linnean Society of London, has called attention to the extensive changes which a strict adherence to the laws of priority would cause in the generic nomenclature of butterflies; and quite recently has put the same into practice in his catalogue of these insects.