138 



U. S p. E. E. EXP. AND SUKVETS — ZOOLOGY — GENEEAL EEPOET. 



darker centres. The tail feathers are black in their middle portion and tipped with white, 

 this decreasing until there is none in the median ones. 



Two males, apparently not quite mature, (3942, 6050,) have the ruff shorter ; the scale 

 feathers dimmer and more of an orange red. They are also rather smaller than the others. 



Sometimes the metallic scales encroach on the sides of the head, so as apparently to cover 

 them. There is, however, always a narrow plain line hehind the eye. The ruff varies consid-- 

 erably in length with the specimen. There is no trace of cinnamon or rufous on any of the 

 feathers in either sex. 



The only North American species to which the male of this bird bears any resemblance is the 

 A. costae, which has the same metallic crown and other generic features. The latter^ however, 

 is much smaller ; has the metallic reflections varied chiefly violet, instead of nearly uniform 

 purplish red. The tail is much less deeply forked, the depth being only about 0.10 of an inch, 

 instead of 0.32 ; the outer feather is much narrower. The females of the two, however, appear 

 to be distinguishable only by their relative size. The absence of rufons and the rounded, not 

 graduated, tail always separates the female of anna from that of >S^. ru/us. The larger size is the 

 chief distinction from the female A. costae, while the Size and less acutely pointed outer tail 

 feathers distinguish it from the female T. colubris. 



List of specimens. 



ATTHIS COSTAE, Reichenbach. 



Ornismyacostae, Bodrcier, Rev. Zool. Oct. 1839, 294. (Lower California.) — Ib. Ann. Sc. Phys. et d'Hist. Nat. 



dc Lyon, 1840, 235 ; tab. ii. — Fretost & Des Murs, Voyage de la Venue, Zool, I, 1855, 194. 



Atlas, tab. ii, f. 1, 2. 

 Selasphorus costae, Bon. Conspectus Avium, I, 1850, ^2. 

 Jitthis costae, Reichenbach, Cab. Jour, fiir Orn. Extraheft, 1853, 1854. 

 Calypte costae, Gould, Mon. Humming Birds. 



Sp. Ch. — Tail very slightly emarginated and rounded ; exterior feather very narrow, and linear. A very long ruff on each 

 side of the throat. Head above and below, with the ruff, covered with metallic red, purple, violet, and steel green. Remaining 

 upper parts and sides of the body green. Throat under and between the ruffs, side of head behind the eye, anal region and 

 under tall coverts whitish. Female with the tail rounded, scarcely emarginate ; barred with black, and tipped with white 

 The metallic colors of the head wanting. 



Length, 3.20 inches; wing, 1.75; tail, 1.10; bill, .68. 



Hab. — Southern California and Colorado Basin, (Monterey, Neboux.) 



Of this beautiful humming bird only a single pair has hitherto been collected hy any of the 

 expeditions, and these are not sufficiently perfect to furnish a satisfactory description. The size 

 is about that of the common ruby-throated humming bird. The bill is, however, longer and 

 more slender every way. The wings are falcate ; the first quill especially curved, although its 

 outlines are parallel to near the tip, which is not acuminate. In the male the tail is slightly 



