PREFACE. IX 



have been most difficult and laborious, but with regard to 

 many rare and inaccessible publications it would have been 

 impossible. The list furnished by M. Agassiz is therefore 

 substantially produced here, but it has undergone a great 

 amount of careful revision and correction. Several thousand 

 additional titles, selected with great care, have also been 

 added, either by myself or under my immediate inspection. 

 These are principally extracted from British scientific perio- 

 dicals, with whose contents continental naturalists are too 

 imperfectly acquainted. Many of these titles had been already 

 extracted at second-hand by M. Agassiz from French and 

 German journals where they are translated, and the works 

 of many British writers consequently appeared in a foreign 

 dress. In such cases the original English title has been sub- 

 stituted, and a reference made to the foreign work where the 

 translation appears. In some instances however I have not 

 had an opportunity of verifying such titles with the originals, 

 and they consequently still remain in the list in their exotic 

 form. 



In the case of very short or unimportant communications, 

 a certain amount of discretionary power was indispensable. 

 Our popular " Magazines" of Natural History teem with tri- 

 fling notices, often anonymous, sometimes brief and indefi- 

 nite, sometimes wordy and inflated, but which do not contain 

 a single fact of scientific importance. To have recorded all 

 such in our list would have added bulk but not value, and 

 they have therefore been in general omitted. But I have 

 always endeavoured to render due justice to every properly 

 authenticated statement, however brief, of a new or import- 

 ant observation in Zoology or Geology. 



Wherever it has been practicable, the lists of each author's 

 writings have been forwarded to him for correction before 

 sending them to the press, and the works of living British 



