INTRODUCTION. XI 



that Benson's genus, the acouracj' of -which has been hitherto overlooked 

 by authors, must supersede tliat of Gray's. 



The generic name llydrohia, founded by Hartmann in 1821, was used 

 by Leach in 1817 for a Coleopterous insect, and is consequently not 

 available ; so that d'Orbigny's Paludestrina * is suggested to take its 

 [)lace. The family name Hydrobiidoe is also changed to that of Paludes- 

 trinidae. The next point of importance affects M. Cossmann's generic 

 name Diastictus of 1888, which had been utilized by Mulsant t in IS-li! 

 for a Beetle. It is with much pleasure that the author changes this to 

 Cossmannia, in honour of M. Maurice Cossmann of Paris, the able writer 

 of the " Catalogue Illustrd des Coquilles Fossiles de I'Eocune des Environs 

 de Paris," published by the Koyal Malacological Society of Belgium, four 

 parts of which have been issued, the remainder being still in progress. 

 It differs from all other works of its nature that have yet appeared, inas- 

 much as the particular horizon for each species is duly quoted — an item 

 of the greatest importance to the systematic palteontologist. 



The name of Deshayes's genus Mesosioma of 1861 was used by Anton 

 Dugcs t in 1830, and again by A. S. Orsted § in 1844, for a genus of the 

 group Annelida, and Cerithioderma is suggested to replace it, this being 

 a shell of remarkably similar characters. 



Verrill's name Ceritliiella is here adopted for Sars's Lovenella of 1878, 

 preoccupied by Hincks |i ten years previously for a Coelenterate animal. 



Hartmannia IT has been recently proposed to take precedence of Pomatins 

 of Hartmann, 1821, because of its having been used by B. Studer in 1789 

 for a totally different shell. The generic name of Callia, J. E. Graj-, 

 1841, was previously employed for a Beetle by Serville ** in 1835 ; for 

 this it is proposed to substitute the new name of Ccdlianella. 



Proserpina of G. B. Sowerby, 1839, had been used for a Lepidopterous 

 insect by Hiibner tt in 1816, and therefore cannot be retained, Despoena, 

 another name, being suggested to replace it, which will result in the family 

 name of Proserpinidffi being superseded by Despoenidse. 



The name of Loven's genus Cylichna of 1846 was applied by Bur- 



* Siuce the sheet containing uiy decision in this matter was in type, my friend 

 Mr. E. A. Smith has published similar views on the subjects in the ' Journ. Ooucho- 

 logy,' 1891, p. 331. 



t Hist. Nat. Col. France, 1842 (Lamellicornes), p. 318. 



X Ann. Sci. Nat. 1830, vol. 21. p. 78. 



§ Ent. Syst. Plattwiirmer, 1844, p. (i7. (8to. Copenhagen.) 



I Hist. British Hyd. Zoophytes, 1868, vol. i. p. 177. 



1[ Annals, 1891, ser. (5, vol. vii. p. 346. 



** Ann. See. Entom. France, 1835, vol. iv. p. 60. 



tt Verzeichniss Schmett. 1810, p. 57. " 



