IV INTRODUCTION". 



The Gallery has been still further enriched by the purchase 

 of the very numerous and beautiful specimens of Fossil Fishes 

 from the Cretaceous Limestone of Hakel and Sahel-el-Alma, 

 in the Lebanon, obtained through the persevering and energetic 

 labours of the Rev. Prof. E. P. Lewis, M.A., F.G.S., of the 

 Syrian Protestant College, Beirut. 



Arrangement. — The Collection, which contains about 450 

 genera, and 1250 species, commences on the left hand on 

 entering the Gallery, the Wall-cases being used for the larger 

 specimens, whilst the smaller are arranged in the nearest 

 Table-cases. 



The names of the orders and families are printed in bold 

 and conspicuous type and repeated in each Case, those of 

 the genera being also repeated upon smaller labels. 



It has been found more convenient to arrange the Collection 

 zoologically, rather than stratigraphically. 



Every specimen bears, in addition to the genus, species, and 

 author's name, the name of the formation and the locality 

 from which it was obtained ; and, if presented, the name of 

 the donor. 



Moreover the fishes of the older rocks nearly all belong 

 to families and genera which are now quite extinct. The 

 Plagiostomi — Sharks and Pays — however, offer a remarkable 

 exception, being an order of Fishes whose persistence in time 

 probably exceeds that of any other vertebrate type ; whilst in 

 the Dipnoi, one family at least — the Ccratodi — has come down 

 to our time from the Devonian epoch, apparently but little 

 modified in the long lapse of geological ages. 



Peferences will be found, at the end of the Guide, to the 

 various works in which figures and descriptions are given of 

 specimens preserved in the Collection. 



