SUPPLEMENT. 



So many new treatises in different languages and such 

 a mass of fresh observations have incessantly poured 

 in upon me since the first volume of this work appeared 

 (now seven years ago), that another volume would 

 scarcely suffice for the additions, corrections, and expla- 

 natory remarks which I have noted in my interleaved 

 set of the volumes already published. I must therefore 

 endeavour to compress these notes into the smallest 

 possible compass ; and I hope my numerous correspon- 

 dents will pardon me if I do not give all the valuable 

 information which they have kindly contributed. My 

 critics will perhaps not be offended by my silence. But 

 as to two of them and I say it in the most friendly 

 spirit I would recommend Professor Eomer to compare 

 a sufficient number of specimens from the Atlantic and 

 Mediterranean before he again asserts positively that 

 Tapes geographicus and T. pullastra are not the same 

 species ; and if Herr Weinkauff would consult the ori- 

 ginal work of Da Costa, he would find that Donax vit- 

 tatus and other species were really described by him in 

 the strict Linnean method. In order to save space, the 

 letter E will denote exotic or extra-British habitats, and 

 F the localities for upper tertiary or quaternary fossils. 



Vol. I. Introduction, p. xxv, line 6 from bottom, for " three 

 millions " read " one million." 



P. xxxii, 1. 17 from top, for " foot " r. " rood. 

 P. xxxvi, Aplysia is not a Nudibranch. 



