CHERRIE: ORNITHOLOGY OF THE ORINOCO REGION. 213 



chestnut, the darker markings overlying the others. Ovate in form, 

 the eggs measure 32.5 x 24.5 ; 33.25 x 24 ; 34 x 24 ; 33 x 24.25 and 32.5 x 

 24 mm. respectively. 



CYANOCORAX CAYANUS (Linnaeus). 



Corvus cay anus L., Syst. Nat. ed. 12. I. 1766. p. 157. 

 Cyanocorax cayanus Berlepsch & Hartert, p. 34. 



According to Berlepsch and Hartert, Klages obtained specimens at 

 Suapure and Andre at La Pricion on the Caura. None were observed 

 by the writer on the Orinoco proper. 



TYRANNIDAE THE TYRANT-FLYCATCHERS, KINGBIRDS. 



Sixty-nine species and subspecies of Flycatchers are included in the 

 present list. Several, however, such as Ornithion inerme, Tyrannulus ela- 

 tus, Myiopagis viridicata viridicata, M. gaimardi, M. flovivertex, and 

 M. cinerea might better be placed with the Cotingidae. But as they were 

 included in my original "key" to the flycatchers they are so retained. 



Many of the flycatchers are conspicuous in the llanos districts of 

 the Orinoco region, conspicuous alike for their harsh cries, their brilliant 

 colors (particularly bright yellows) and extraordinary nesting habits. 

 As nest builders they have few rivals, certain species constructing deli- 

 cate lichen covered affairs as tiny and trim as those of some humming 

 birds, others whose nests might serve as models for the weaver-birds, 

 and again the great bulky grass nests, such as those of Pitangus, placed 

 in the tree tops are prominent objects in the landscape. But not all are 

 birds of the open llanos, many are quiet and retiring both in dress and 

 disposition. These must be sought for in the semitwilight of the thick 

 forest where they flit about, as silent as the shadows, in the under- 

 growth. 



KEY TO THE GENERA, SPECIES AND SUBSPECIES OF TYRANNIDAE. 



a. Tail very long and deeply forked Muscivora tyrannus. 



a'. Tail not unusually long or deeply forked. 



b. Chest barred with olive brown Onychorhynchus coronalus. 



b'. Chest not barred. 



c. Under parts more or less streaked with dusky or blackish. 



d. Wing less than 60 mm Todirostrum maculatum. 



d'. Wing more than 60 mm. 



. A well marked black or blackish auricular stripe. 



/. Inner web of tail-feathers broadly edged with rufous Myiodynastes maculalus macu- 



lalus. 



f. Inner webs of tail-feathers not broadly edged with rufous, 

 g. Upper tail-coverts broadly edged with rufous; inner webs 



of tail feathers not edged with rufous Empidonomus varius. 



g'. Upper tail-coverts not edged with rufous; inner webs of 



tail-feathers narrowly edged with rufous Legatus albtcollts. 



e'. No black or blackish auricular stripe ( d" im. or 9 ) Pyrocephalus rubinus satura- 



tHt. 



