IREDALE : srNOPSES CONTENTS BRITISH MUSEUM. 301 



commencement reading: "The following List exhibits the series of 

 genera of Mollmca at one view, and the numbers indicate the Table 

 Cases in this Gallery, in which the genera in the collection are placed." 

 The succeeding list extends from pp. 124-30, and almost exactly 

 agrees with the 1840a list. 



The forty-fourth edition, dated 1842, however, presents a trouble- 

 some complication. The general account is entirely rewritten, and 

 diagnostic remarks are given of the genera, including most of those 

 indicated as new in the forty-second edition, and an extended list 

 follows. The remarks appear to me to be insufficient to establish the 

 names, but in order that they may be fairly considered I reproduce 

 them on pp. 302-9. 



The forty-fifth edition was published in 1843, and on p. 10 the 

 following note appears: "For an explanation of the method on 

 which the Zoological Collection is arranged, and a list of the genera, 

 see a small work called the 'Guide to the Zoological Collection', 

 sold in the Hall, where may also be had a ' List of the Species 

 of Mammalia', with the Synonymes." 



Herein the matter relating to the "Shells of Molluscous Animals" 

 is reduced to 4i pages, and the list is omitted. The subject 

 is rewritten very briefly in the following manner: "Table 17. 

 The Top Shells \TrochuH) and their allied genera, as the pyramid 

 {Pi/ra»iis). The vosar j [Clanffuliis Pharaonictis). The jujube berry 

 {Trochus Ziziphorus). The iris or rainbow eavdro-p (Can f herns Iris), 

 from New Zealand. The button shell {Rotella lineolata). The 

 strawberry [Monodo?ita). The gold button {Livona aurea), which is 

 peculiar for the lii;ht golden colour of the pearl. The dolphin 

 {DeJphinula).'''' This is exactly repeated in the forty-sixth edition 

 (published in 1844), which contains none of tlie names credited by 

 Gray himself to "1844". In the forty-fourth to the sixty-third 

 (the last) editions there is nothing relating to the sj'stematic study 

 of Molluscs worthy of note. 



It has now been shown that the forty-fourth edition, published in 

 1842, is the most important one, and needs careful con.«iiieration. 

 It is also obvious that tlie diagnoses there given cannot be literally 

 accepted, as most of them are merely comparative ones, and the fact 

 must not be overlooked that Gray used many of the common generic 

 names in a different sense to that hereafter assigned to them. Thus 

 ill the Proo. Zool. Soc. article we are told, for instance, that Vermetus, 

 Gray, 1840, was not Vermetus, Adanson; E7italis not Entalis, Def ranee; 

 OvatUla not Oratilla. Bivon. ; Pof amides not Potamides, Erongn. ; and 

 Clathrus not Clathrus, Oken, 1815. 



It is on account of such difficulties that I would advocate the 

 rejection of the whole of the names used in this edition, and date 

 them all from 1847; but, as this is simply an individual opinion, 

 I am givin<; the whole of the diagnoses so that this matter may now 

 be fully discussed, and a definite policy of rejection or acceptance 

 adopted. There appear to be few alterations necessary tlirough the 

 adoption of the former policy, which seems to me to best favour 

 accuracv. 



