118 DENDROCOLAPTID^. 



than perhaps any group of the American Avifauna except the 

 Tyrannidce. 



The Dendfocolaptina' are distributed all over the Neotropical 

 Eegion except the Antillean Subregiou. 



Key to the Genera. 



A. Bill more or less compressed. 



a. Bill shorter than the head. 

 a'. Gonys straight ; hill weak. 



j Tail longer, more spiny 35. Sittosomus, p. 119. 



I Tail shorter, less spiny 36. Margaeohnis, p. 121. 



b'. Gonys ascending; hill strong. . 37. Glypiioeiiynchus, p. 124. 



b. Bill as long as or longer than the 



head. 



c'. Gonys ascending 38. Pygarrhicus, p. 126. 



d'. Gonys straight. 



a". Bill longer, slenderer. 



I Commissure incurved . . 39. Dendeornis, p. 127. 

 1 Commissure straight. ... 40. Dendeoplex, p. 138. 

 b". Bill shorter, stouter : 



less broad at base 41. Dbndeexetastes, p. 140. 



; more broad at base 42. Hylexetastes, p. 141. 



Gonys more or less incurved, 

 c". Bill rather longer than head. 



j Bill stout; size large 43. Xiphocolaptes, p. 142. 



I Bill slender; size small. . 44. Picolaptes, p. 146. 

 d". Bill twice as long as head, 

 ft'". Bill slightly broadened at 



the base 45. Nasica, p. 150. 



b'". Bill compressed through- 

 out : 



j thicker, gently curved. 46. Deymoenis, p. 157. 

 I thinner, much curved. 47. XiPiiOEHYNCHus, p. 158. 

 Bill more or less depressed, expanded. 



( Bill less widened 48. Dendeocincla, p. 162. 



■ Bill more widened 49. Dendeocolaptes, p. 169. 



35. SITTOSOMUS. rr 



Type. 



Sittasomus, Sw. Zool. Joitrn. iii. p. 355 (1827) S. erithacus. 



Sittosomus is a peculiar form of nearly uniform plumage, in which 

 the beak is short and almost Sylviine, and the tail long with the 

 ends of the stiffened stems of the rectriccs projected far beyond 

 the termination of the webs, and but slightly clothed with spiny 

 barbules. Three species are distinguishable, which together extend 

 from Southern Mexico to Argentina. 



Key to tlie Species. 



A. Throat not spotted. 



j Head and body beneath yellowish 1. erithacm, p. 119. 



) Head and body beneath olivaceoii^i 2. olivaceiis, p. 119. 



B, Throat spotted 3. stictolamus, p. J 20. 



