PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 477 



Zoo-geograpmcal province. 



% . 

 x a 

 = H 

 s 



> 



Tail. 



X 



^ ■ 

 rH 



Width Of bill 

 at base. 



Depth of bill 

 at base. 



T. 



Middle toe. 



Fork of (ail. 



Brazilian 



7 



4. Gl 



4. 09 



.71 



.47 .30 



. 72 



.55 



.69 



Amazonian (including Guiana) 



5 



4. 4S 



3. 97 



.G7 



.45 .31 



.05 



.53 



.61 



Columbian (including "Western Ecuador) 



14 



4.47 



4. 03 



.08 



.46 1 .28 



.09 



.53 



.61 



Central American 



6 



4. G7 



4. 08 



.05 



. 45 ! . 29 



.72 



.54 



.56 



Mexican (including Guatemala and Honduras). 



13 



4. GO 



4.04 



.68 



.43 ■ .31 



.73 



.57 



.42 



The result would of course be somewhat changed with a different 

 proportion of specimens representing the several regions; hut in any 

 case it would probably be shown, that the general dimensions increase 

 in proportion to the distance of the locality from the equator, and that 

 the tail is most deeply emarginated in the most southern examples, 

 becoming gradually less forked toward the northward. 



7.— TYEANNUS ALBIGULAEIS. 



Tyrannus albofjularis, BURM., Th. Bras. II, 1S56, 405 (northern forest-district of Brazil). — 

 Pelz., Orn. Bras. 1871, 117 (Goiaz, Cuyaba, Matogrosso, and S. Vicente). 

 Tyrannus albigularis, Finscii, V. Z. S. 1670, 572, in text sub T. mdanchoUcus 

 (critical).— Scl. & Salv., Norn. Neotr. 1873, 53. 



" Musckapa albigula, Natterer, Catal. Mac." (Pelzcln). 



Sp. Cii. — "Head gray; middle of the crown fire-red; back green; 

 throat white; breast and belly yellow; wings and tail more brownish, 

 the feathers with lighter edges. 



"A little smaller than the preceding species [T. melarwholwus], more 

 slender and of more graceful form, the beak especially. Crown, as far 

 as the eye, and nape light whitish gray, rictal region ("Zugelgegend") 

 and upper half of the ear-coverts blackish, the cheeks and the lower half 

 of the ear-coverts as well as the throat, pure white. Back and lesser 

 wing-coverts ("Achselfedcrn") olive-green, the upper tail-coverts brown- 

 ish. Wings and tail-feathers grayish brown, the first narrowly edged 

 with whitish green, the latter with rust-yellow, particularly towards the 

 base ; the inner edge of the wing of the same color, but broader, wanting 

 on the tail-feathers. Only the three first primaries attenuated and emar- 

 ginated, but the tip ("Absatz") much shorter and blunter [than in T. mc- 

 lancholicus]. Breast, belly, thighs and anal region lemon-yellow; there 

 is no gray shade on the breast, but the yellow color with greenish tint 

 extends here as far as the neck. Beak and legs blackish brown, iris 

 brown; the beak on the whole smaller, considerably shorter, with a dis- 

 tinct though blunt ridge and moderately convex ; . . . . the toes longer. 



"Total length 8", culmen 7'", wings 4", tail in the middle 3", along 

 the outer feather 3" 4"', commissure 8'", middle toe without claw (V". 



"The species inhabits the northern forest-region of Brazil, near liahia, 

 and Pernambocco ; it entirely resembles the preceding in its habits and 



