146 DENDEOCOLAPTID^. 



II. Synallaxinse ; 



III. Philydorinae ; 



IV. Sclerurinae; 



V. Dendrocolaptinse : 

 the subordinate characters being taken from the size of the bill and the length of the 

 tarsus. 



When the definitions of these subfamilies are submitted to test, we find that they do 

 not give satisfactory results, so that we are obliged to modify them considerably by 

 introducing the shape and structure of the nostrils as a character of importance ; the 

 relative length of the hallux is also useful as a diagnostic feature. 



We cannot here go into all the modifications involved in Mr. Sclater's classification 

 when the shape of the nostrils is taken into consideration, but in illustration we note 

 that when the nostrils of Pseudocolaptes are examined it will be seen that they are 

 linear and overhung, and not open and oval. This character places Pseudocolaptes in 

 the Synallaxinae and not with the Philydorinae. The Philydorinae are also affected by 

 this character, and great changes must be made in the grouping of a large number of 

 South-American genera, and even the species of some genera must be re-examined — as, 

 for example, Thripcyphaga, which, as exemplified by its type T. striolata, has an open 

 oval nostril and is allied to Philydor ; but all the other birds associated with it have 

 linear overhung nostrils, and must be placed in the Synallaxinae, perhaps in the genus 

 Placelodomus. 



The Dendrocolaptidae of Mexico and Central America may be divided as follows : — 



A. Rectrices laxse, rhachidibus ad apicem haud rigidis. 



a. Nares lineares et membrano obtectse ad marginem inferiorem 



fossse nasalis positse Synallaxinae. 



b. Nares apertse, ovales, ad finem fossae nasalis sitae Philydorin^. 



B. Rectrices rigidse, rhachidibus prolongatis, acutis. 



c. Hallux longus fere digitum medium sequans. 



a'. Nares apertse, ovales Sclerurin^. 



v. Nares lineares, membrano obtectse Margarornithin^. 



d. Hallux brevis, quam digitum medium multo brevier. 



c'. Nares lineares, arcuatse, membrano obtectse Glyphorhynchin^e. 



df. Nares apertse, ovales DENDRocoLAPTiNiE. 



The Central- American Synallaxinae as thus defined contain three genera including in 

 all six species ; the Philydorinae four genera and fifteen species ; the Sclerurinae the genus 

 Sclerurus, with three species ; the Margarornithinae the genus Margarornis, with two 

 species ; the Glyphorhynchinae, Glyphorhynchus, with one species ; and the Dendro- 

 colaptinae seven genera and nineteen or, perhaps, twenty species : the total number 

 of genera being seventeen, with forty-six or forty-seven species. Of the genera not 

 one is peculiar to Central America; but of the species twenty-nine are not found 



