REMARKS ON THE GENUS SULA. 305 



The fact is that this genus has never I believe been properly 

 worked out, and until some one is in a position to do this, we 

 shall always remain in doubt as to many essential points, such 

 as the true number of species, the changes of plumage, the varia- 

 tions in the colours of the soft parts and the like. 



Unfortunately, what is requisite for a proper investigation of 

 this small and well-marked genus, is a really large series of 

 specimens from all parts of the world correctly sexed by dis- 

 section, witli dates, localities, and colours accurately recorded. 



Such a series exists in no one locality ; the great majority 

 of the specimens in museums (aud even these are not numerous) 

 have not been reliably sexed, and in not a few cases their 

 origin even is doubtful. 



The only authority to whose works I have access, who has of 

 late years dealt with this genus as a whole, is Professor 

 Schlegel in the Mus. Pays. Bas. Pelecani, p. 37, et seq, July 1863. 



He admits 



1. Sula bassana, Lin. 



2. Sula serrator, Banks. 



3. Sula capensis, Licht. 



4. Sula cyanops, Sundev. 



5. Sula piscatrix, Lin. 



6. Sula australis, Stepli. {fiber apud ScJd. et auct. nee Lin.) 

 But besides these, other authorities keep other species dis- 

 tinct, viz. — 



7. 2 A. Sula lefevrii, Baldamus. 



8. 4A. Sula dactylatra, Less. 



9. 5A. Sula variegata, Tschudi. 



10. 6A. Sula parva, Gm. 



and a careful examination of what has been put on record 

 in regard to this genus, leads me to believe that it will eventually 

 prove to contain even more species. 



When high authorities, like Finsch and Hartlaub on the one 

 hand (Orn. Polynes. 260), and Salvadori (Ucc. di. Borneo, 

 369) on the other, with the museums and libraries of Europe 

 open to them, contradict each other point blank as to whether a 

 supposed species {variegata) is identical with another {piscatrix), 

 or absolutely distinct, and when almost every one who has 

 written any thing original about Boobies (and not merely copied 

 existing records), traverses or contradicts something that some 

 one else has said, it would be absurd for me, in a distant colony, . 

 with a meagre library, and no specimens of this particular 

 group, to speak of, in my museum, to pretend to be able to put 

 matters on a more satisfactory basis. 



All I can do is, following what others have written, to give 

 an extemely brief sketch of the several species of the genus 



