rest assured that neither pains nor expense will be sp; rec 

 ensure the correctness, completeness, and beauty of the work. 

 The plan of the work is as follows : — it will consist of a 

 complete series of Monographs of Genera of Shells. All 

 the species and varieties of each genus will be described 

 and figured. The essential characters will be given in latin. 

 The explanations and general information will be 

 pressed in English. The figures of average sized shells 

 will be reduced to half the real diameter ; those of larger 

 size will be still further reduced ; and those of small size 

 will be represented of the natural dimensions. The size of 

 the book is Imperial octavo. The paper, printing, engraving 

 and colouring of the best description. A part, containing 

 several Monographs will appear every third month, o\ 

 oftener if possible, the price of each part to depend 

 the number of figures which it contains, at the rat*, i 

 one penny for each figure. 



The 2nd Part will appear on the 1st ov August, 



CONCHOLOGICAL ILLUSTRATIONS, 



Or, figures of hitherto unfigured recent Shells, Part 1 to 200, 



Prick, Is. 6d. each, 



May now be had with Indices complete. None of the Genera contained in 

 this work will be given in the Thesaurus until all the other Genera are 



exhausted. 



SOWERBY, Naturalist, 

 No. 50, GREAT RUSSELL STREET, BLOOMSBUR-Y. 



2-7 



