TYRANT-BIRDS. 469 



according to the more or less obvious resemblance they may have to the true (osci- 

 nine) chats, wrens, or flycatchers. 



The family is not difficult to define by means of external characters, as the tyrant- 

 birds have exaspidean tarsi, and the outer and middle toes united only at their base, as 

 in most Passeres. As an additional character may be added that the bill is more or 

 less hooked at the .tip, if we consider the genus Oxyrhynchus entitled to family rank 

 on account of its curious straight and pointed, lengthened conical, and somewhat star- 

 ling-like bill. The anatomy of the OXYRHYNCHIDJE, however, is too little known to 

 allow any certain conclusions, and if the form of the bill alone is taken into consider- 

 ation such a separation seems hardly defensible in view of its great variability in the 

 Tyrannidae proper, in. which, without dissent, are included birds with bills as different 

 as that of a shrike, a warbler, and a flycatcher. The species 6f Oxyrhynchus are only 

 two, one, O.frater, from Costa Rica and Veragua, the other from Brazil. The colora- 

 tion resembles that of several other tyrant-birds, being green with a fiery orange 

 crown patch. 



The systematic arrangement of the tyrants is a matter of considerable doubt, as 

 the numerous forms on one hand show extreme development of certain characters, 

 while, on the other hand, they grade insensibly into each other, being connected all 

 around by intermediate forms. We shall, therefore, not attempt here to define any 

 sub-families, contenting ourselves by briefly mentioning the most noteworthy forms. 



Notwithstanding the fact that the tyrants are chiefly tropical birds, only one tenth 

 of the whole number entering the fauna of North America, the great bulk of the 

 family is made up of very unsightly birds which are not particularly attractive, either 

 by their coloration, by their form, or by their voice. The fundamental coloration, so 

 to speak, seems to be gray, darker above, whitish beneath, but a common modification 

 is that the whole plumage is washed with yellow, which causes the back to become olive 

 and the under surface to be more or less pure yellow. A very common character is 

 the shining yellow or red crown patch on top of the head, more or less hidden when 

 the feathers are not raised. As this bright spot is invariably found in both sexes, the 

 question has been raised whether it is an ornament acquired by sexual selection, or 

 whether it may not have some other object. Mr. Charles W. Beckham has made the 

 following suggestive observations on our common king-bird, or bee-martin (Tyrannus 

 tyrannus) : 



" Several years ago, in May, I saw one of these birds occupying an exposed perch 

 on a pear-tree in bloom, about which many bees were darting. Several times I ob- 

 served that the bird caught the insects without leaving his perch by quickly turning 

 his. head and 'grabbing' them. My attention being thoroughly aroused, I noticed 

 that many of them seemed to fly directly towards him ; the majority appearing to 

 * shy off ' at a short distance and change their coui*se, but very few that came within 

 reach escaped him. The question naturally suggests itself : Did the thrifty Hymen- 

 optera mistake the fully displayed orange red crown (I could see that the crest was 

 erected) for a flower? Once since I have observed the same phenomenon, but not as 

 well as upon this occasion. Mr. C. C. Nutting, who has spent considerable time 

 studying the birds of Costa Rica and Nicaragua in their native haunts, states that he 

 has seen Muscivora mexicana perched upon a twig, and waving its curious and bril- 

 liant fan-shaped crest after the manner of a flower swayed by a gentle breeze, and 

 thus attracting insects within reach." 



Not all the Tyrannidae, however, are plainly colored, nor is the family without such 



