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Rh gotten, till some meddling bibliographer disturbs the peaceful oblivion in which their claims lie buried.

When Otho Fridrich Müller, in 1785, definitely established the genus Lynceus, which he had already brought forward in his 'Prodromus' of 1776, he assigned to it nine species, the first being L. brachyurus, the second L. sphæricus, a variation from the order adopted in the earlier work. That these nine species have since been distributed among numerous genera is well known; but in this distribution the true position of the genus Lynceus has been lost sight of. Since Müller singled out no species as typical of the genus, it was at the outset open to anyone, in dividing the genus, to allot the original name to which species he pleased. No stress whatever can, in my opinion, be laid on the circumstance that Latreille, in his 'Considérations générales,' pp. 91, 421 (1810), mentions ' Monoculus brachyurus, Fab.," as a typical example of Lynceus. He was not discriminating between species and species, and was pretty evidently without the knowledge requisite for doing so. So far as he is concerned all the nine species remain exactly where Müller placed them. There is no hint of an idea that any ought to be transferred to a separate generic division. It is different with Dr. Leach, for he, in 1816, definitely began that partition of the genus which has since been greatly developed. When describing the Crustacea as a division of the Annulosa in the 'Encyclopædia Britannica,' p. 416 (1816), Leach assigns to Lynceus the single species brachyurus, and to a new genus Chydorus the single species sphæricus. The inference, then, can scarcely be escaped that, whatever else happens to these two genera, neither can be upheld without at least including in it the species assigned to it by Leach. Desmarest, in 1825, rejects Chydorus, upbraiding Leach for having established it merely upon Müller's error in regard to the antennæ. Desmarest himself, whose acquaintance with the subject was not very profound, includes five species under Lynceus, but says never a word about L. brachyurus. His objection to Chydorus has been overruled, and with good reason, since, however weak the distinction drawn by Leach, the application was put beyond doubt by the references which he gives to the species above mentioned. Subsequently Dr. Baird distributed six of Müller's species over the genera Eurycercus,