NATURAL SCIENCES OF PHILADELPHIA. 59 



the point of the wing. The fork of the tail is less than a third of an inch. In 

 neither sex of C. Henryi is there any rufous mottling on the primaries ; and 

 thus one conpsicuous alar spot is white in hoth sexes ; and is moreover much 

 nearer the bases of the primaries, being 3^ inches from the point of the wing : 

 so that when the wing is folded the spot is anterior to the ends of the secon- 

 daries. The reverse is the case in C. Texensis ; and these points will always 

 separate the two species, even when small female C. Henryi is compared 

 with large male texensis. I do not know if the female texensis always has a 

 white throat. 



I am unable to discuss the relationship of the C. branliensi* 6m., and in 

 adopting the name texensis I am following Mr. Lawrence's authority altogether. 



HALCYONlDsE. 



56. Ceryle alcyon (L. ) Boie. 



Common summer resident. Arrives April 10th ; remains until November. 

 Generally distributed over the various streams of the Territory. 



(57.) Ceryle Americana (Gm.) Boie. 



Observed at several points on the Colorado River between Forts Mojave and 

 Yuma, which I believe is the first recorded instance of its occurrence in the 

 Uuited States elsewhere than in the valley of the Rio Grande. 



COLOPTERID.E. 

 58. Tyrannus vociferans Swains. 



Abundant summer resident. Arrives third week in April ; remains until 

 latter part of Sept. Found in every sort of locality. 



Adult individuals of the same sex hardly vary appreciably in size ; and the 

 colors are exceedingly constant. Males average from 9* X 16 - 5 to 9"25 X 

 16 - 75 ; females measure about 8-75 X 16. Iris brown. Bill and feet black. 

 Mouth livid flesh color. 



The young of the year in July and August differ materially from the adults. 

 The mouth and some part of the lower mandible are bright yellow. The feet 

 are light colored instead of black. The primaries are not attenuated near 

 their tips. There is no trace of the red in the crown. Tue outer web of 

 the exterior tail feather is barely appreciably lighter than the rest. The wing 

 coverts are strongly margined and tipped with pale rufous ; the quill feathers 

 less conspicuously edged with yellowish white. The back is nearly pure dull 

 brown, concolor with the head instead of being olive gray in contrast with the 

 plumbeous head. Below the two ages are nearly alike ; but the yellow is 

 sometimes so pale as to be dull sulphury white ; while the breast is rather 

 brown than plumbeous. The chin is always conspicuously pure white. 



(59.) Tyrannus verticalis Say. 



A bird which in its extensive wanderings includes Arizona, though that 

 country cannot be considered as properly a part of its habitat. Dr. Cooper 

 has taken it at Fort Mojave, and throughout Southern California. I have 

 never met with it at Fort Whipple, where vociferans is so very abundant. 



60. Myiarchus MExicANCS (Kaup.) Baird. 



Common summer resident. Arrives third week in April; remains until 

 middle of September. Seldom found in the pines, preferring ravines, hill- 

 sides, creek bottoms, etc. Some winter as high in the Colorado Valley as 

 Fort Mojave. (January; Cooper.) Iris brown. Mouth livid flesh color. Bill 

 and feet black. Moult through July and August. 



At Fort Whipple .young birds were first observed early in July. Though 

 not mistakable for any other species, they differ notably from the adults. The 

 head is clear brown, in tolerably strong contrast to the color of the back, which 

 latter is lighter and duller than that of the adult. All the wing coverts are 

 so widely edged and tipped with light rufous as to give the prevailiug color 



1866.] 



