Letters, Announcements, S^c. 341 



vately printed in 1840; a second edition (also privately printed) 

 of this work was called for in 1841, to which an Appendix was 

 added iu 1842. 1232 divisions were recognized in this last 

 edition with its Appendix. 



In 1844 the great work on the Genera of Birds was com- 

 menced iu conjunction with the late Mr. Mitchell, who under- 

 took the superintendence of the engravings. This standard 

 work, completed iu 1849, is too well known to need comment 

 here. In 1855 a third edition of the ' List of Genera and 

 Subgenera of Birds ' appeared, in which were incorporated all 

 the additions since the issue of the edition of 1842. Finally, 

 so far as this portion of ]\Ir. Gray's work is concerned, we have 

 the three volumes of the ' Hand-list of Genera and Species of 

 Birds,' the third volume of which was only issued last year. 

 The scope and objects of this final and most laborious under- 

 taking have been fully set forth in these pages, so far as the 

 first two volumes are concerned; the last volume contains the 

 completion of the enumeration of the remaining families, genera, 

 and species, and also a comprehensive index to the whole three 

 volumes, both of generic and specific names. The amount of 

 labour bestowed on this work can be gathered from the state- 

 ment of Mr. Gray's, that of the 11,000 species of birds which 

 are there recognized, no less than 46,000 references had to be 

 made and entered. 



The value of the ' Hand-list ' has been at once recognized by 

 working ornithologists ; and references are so frequently made 

 to its pages as to show that it is constantly and necessarily 

 referred to by every one working at the subject. Its utility will 

 remain for some time to come, indeed until, as is the fate of all 

 such compilations, another ornithologist shall arise endued 

 with Mr. Gray's perseverance, and give us another ' Hand-list' 

 with the references fully extended. Such a task will not readily 

 be accomplished. 



Comparing the early editions of the ' Lists of Genera' and the 

 ' Hand-list,' a fair epitome of the progress of ornithological 

 science from 1840 to the present time might be formed. 



Besides the above works, Mr. Gray's Catalogues of the Col- 

 lections in the British Museum form another scries of useful 



