BIRDS OF NORTH AND MIDDLE AMERICA. 609 



Nidification. — Nest in holes of trees, composed of dried grasses, 

 shreds of bark, etc., Hned mth softer materials, often "ornamented" 

 by addition of a cast-off snake skin. Eggs whitish or otherwise light 

 colored, curiously streaked, longitudinally, with various hues of 

 brown. 



Range. — The whole of temperate and tropical America, including 

 the West Indies but excluding the Galapagos Archipelago and other 

 outlying islands on the Pacific side. (About . thirty-five species, 

 including subspecies.) 



KEY TO THE SPECIES AND SUBSPECIES OF MYIARCHUS.o 



a. Bill relatively narrow and deep, its depth at base of gonys nearly, if not quite, equal 

 to its width at same point. (Myiarchus.) 

 b. Primaries edged, more or less distinctly, with cinnamon-rufous or cinnamon, 

 c. Tliroat and chest deeper gray (no. 8 to nearly no. 7); abdomen, etc., deeper 

 yellow (between straw and canary) ; inner webs of rectrices wholly cinna- 

 mon-rufous, or else with only a narrow line of dusky next to shaft; tarsus 

 relatively shorter (less than one-fifth as long as wing). (Eastern North 

 America, south in winter to Cuba and Colombia.)- .Myiarchus crinitus (p. 613) 

 re. Throat and chest paler gray (paler than no. 8); abdomen, etc., paler yellow 

 (primrose to yellowish white or sometimes even white) ; inner webs of rec- 

 trices not wholly cinnamon-rufous, or else {M. nuttingi and M. brachyurus 

 only) other characters not as in c. 

 d. Outermost rectrix with at least inner half of inner web cinnamon-rufous, the 

 color as deep as on inner webs of other rectrices. 

 e. Inner webs of rectrices with a distinct stripe of dusky extending along 

 shaft for much the greater length of the rectrix. 

 /. Dusky stripe on inner web of outermost rectrix broader, occupying 

 approximately one-third of the width of the web; bill relatively 

 larger (expovsed culmen averaging more than 20 imn.). 

 g. Color of upper parts much darker, with pileum practically concolor 

 with back. {Myiarchus oberi.) 

 h. Larger (wing averaging more than 97 in male, more than 94 in 

 female) . 

 i. Paler wing-markings less distinct, darker in color; color of back, 

 etc., more olive. (Islands of Dominica and Santa Lucia, 



Lesser Antilles.) Myiarchus oberi oberi (p. 617) 



ii. Paler wing-markings more conspicuous, more whitish; color of 

 back, etc., more sooty. (Islands of St. Vincent, Bequia, 

 Carriacou, Union, Prune, Tobago Keys, and Grenada, Lesser 



Antilles.) Myiarchus oberi nugator (p. 619) 



hh. Smaller (wing 92.6 in male, averaging 88.7 in female). (Islands 

 of St. Christopher and Barbuda, Lesser Antilles.) 



Myiarchus oberi berlepschi (p. 620) 

 gg. Color of upper parts much paler, with pileum more or less distinctly 

 more brownish than back. 



a Based on adults only. M. denigratus Cory, from Grand Cayman Island, is not 

 included, no specimen being available at the time the key was prepared. 



11422— VOL 4—07 39 



