iv Foreu'ord. 



the base of the upper mandible through both nianclibles. The length of the tarsus is measured from 

 the enlargement on the front outside of the tibio-tarsal ( /. c, the ' 'knee" ) joint to the more or less obvi- 

 ous beginning of the middle toe. The middle toe is measured in a straight line along the top from 

 the last-mentioned point to the tip of the nail. 



In bringing together the key I have made free and frequent use of the catalogue of birds in the 

 British Museum, and Ridgwaj's Manual of North American Birds, together with the valuable con- 

 tributions to our knowledge of the Hawaiian ornithologv — Aves Hawaiiensis, by Mes.srs. Wilson 

 and Evans, and Avifauna of Laysan, etc. I have also had at hand the published notes of Messrs. 

 Gadow, Dole, Perkins, Stejneger, and others. In addition to the above I have had the pleasure of 

 examining the material in the National Museum at Washington, D. C, the Philadelphia Academy of 

 Science, the British Museum, Tring Museum, and the Jardin des Plantes. To all of these sources 

 of information I would make grateful acknowledgement of the service the>' have rendered. 



WM. ALANSON BRYAN. 



[260] 



