PEESIDENT S ADDRESS. 



181 



An admirable display of soft preparations in spirits, prepared by 

 Mr. W. (x. Ridewood under the superintendence of the Director, or 

 obtained from the Zoological Station at Naples, is also exhibited, 

 comprising N^udibrauchs ; oceanic forms such as Carinaria and 

 Pteropoda ; and a series of Cephalopoda, some of which have been 

 dissected to show the internal anatomy. We are informed that it 

 is intended to add to this very instructive collection a good series 

 of Radulfe, illustrating, both by figures and specimens, the various 

 forms of the lingual teeth in the Glossophora. 



As germane to our special subject I may draw attention to the 

 excellent work carried on now for some years by Messrs. A. H. 

 Foord and Gr. C. Crick in the preparation of a descriptive Catalogue 

 of the Fossil Cephalopoda in the British Museum (Natural History), 

 of which two volumes have already appeared, whilst one is now in 

 the press. The value and importance of this work will be better 

 understood after an inspection of the interesting gallery in which 

 Mr. Crick's labours are concentrated ; a visit to this will well repay 

 the Malacologist. Mr. Crick has endeavoured to carry out in detail, 

 by means of models and illustrations, the structure of the Cephalopod 

 shell. Here, for example, is a figure of a model of his own con- 

 structing to illustrate the mode of growth of one of the most curious 

 of camerated shells of Silurian age, the genus Ascoceras. 



/ 



Ascoceras, as modelled by Mr. G. C. Crick, F.G.S. 



(A) Diagrammatic Section of Nautiloid portion of shell of Ascoceras, showing 



the structiu-e and arrangement of the septa, dt., duct; si., siphimcle. 



(B) Section showing the Orthoceras and Ascoceras stages united (after 



Liudstrom) . 



