_S. alis subdentatis, cinereis (in maribus lineis fuscis variatis); posticis rufis, margine nigro; abdomine pallido, cingulis atris circumdato._ Wings slightly dentated, cinereous (in the male variegated with brown lines); posterior rufous, with a black margin; abdomen pale, with black belts. _Gmelin_ 5. 2375. 13. _Fab. Ent. Sys._ 3. 362. _no._ 21. S. Ello. _Drury_, vol. i. p. 59. _pl._ 27. _fig._ 3. (_male._) _Cramer_, _pl._ 301. D. * * * * * It is in all things better to understand few subjects well than many imperfectly; knowledge may be extensive, but it cannot be sound, if it is at the same time imperfect; and, applying this observation to the present article, it becomes as desirable, where necessary, to illustrate an insect known to Linnaeus, as to regard only the accession of new species. The two insects figured were received from Jamaica by my friend Dr. Leach, and there can be no doubt they are the sexes of one species. The upper is a male, and agrees with Drury's figure and description; the lower insect is a female, of which no representation has been published: as for Cramer's figure, if intended for the former, it is really so bad that it can hardly be quoted as an authority, and it appears to have misled Fabricius, in thinking that the female insect had a brown stripe on the anterior wings, whereas that character is more applicable to the male. The insects I propose retaining under this genus are such as have the body lengthened, pointed, and not bearded at the tip; the antennae but slightly thickened in the middle, and the terminating hook gradual, arched, and not very acute: these comprehend the first section of Latreille's genus, _Sphinx_, and are by him again divided into two groups, the one having the wings entire, the other angulated. * * * * * Pl. 82 [Illustration] TROCHILUS niger, _Black Humming Bird._ * * * * * GENERIC CHARACTER. _Rostrum elongatum, rectum vel arcuatum, flexile, gracillimum, ad basin depressum, mandibula superiore inferiorem amplectente et tantum non obtegente. Lingua jaculatoria, bifida, tubulata. Nares basales, membrana tectae, apertura in longum fissa. Pedes sedentes, minimi. Alae longissimae, subarcuatae, remigibus prioribus longissimis, caeteris gradatim brevioribus._ Typus Genericus _T. Moschitus_ Linn. Bill long, straight or curved, flexible, very slender, the base depressed, the upper mandible folding over, and almost covering the lower. Tongue long, extensible, bifid, and tubular. Nostrils basal, covered by a membrane, and opening by a long slit. Feet sitting, very small. Wings very long, curved, the outer quill longest, the rest gradually becoming shorter. Generic Type _Ruby-crested Humming Bird_ Lath. * * * * * SPECIFIC CHARACTER.