L7NCEU8 AND THE LYNCEIDM. 103 



gotten, till some meddling bibliographer disturbs the peaceful 

 oblivion in which their claims lie buried. 



When Otho Fridrich Miiller, 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. sphcericus, 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 Miiller singled out no 

 species as typical of the genus, it was at the outset open to any- 

 one, 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 ' Considerations 

 generates,' pp. 91, 421 (1810), mentions ' Monoculus brachyurus, 

 Fab.," as a typical example of Lynceus. He was not dis- 

 criminating 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 Miiller 

 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 ' Encyclopaedia 

 Britannica,' p. 416 (1816), Leach assigns to Lynceus the single 

 species brachyurus, and to a new genus Chydorus the single 

 species sphcericus. 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 Mailer's error in 

 regard to the antennae. 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 appli- 

 cation was put beyond doubt by the references which he gives to 

 the species above mentioned. Subsequently Dr. Baird dis- 

 tributed six of Miiller's species over the genera Eurycercus, 



