44 U. S. p. R. R. EXr. AND SURVEYS — ROUTE TO CALIFORNIA. 



the same habits. The nest, built in the hollow of a tree, is composed of grasses, and contains 

 four to six eggs of a pale blue color. 



SIALIA ARCTICA, S w a i n s .—Arctic Blue Bird. 



Sialia arctica, Aw. B. of A. Oct. vol. II, p. 178, pi. 136.— Ib. Fol. pi. 393, figs. 2 and 3.— Nurr. Orn. toI. II. p. 573. 



Met with occasionally in small flocks during the winter season. I saw it in New Mexico, and 

 Colonel M'Call, U. S. A., informed me that in Santa Fe it breeds like our common blue bird, 

 in boxes put up for that purpose by the inhabitants of the city. 



CINCLUS AMEKICANUS, Swains.— American Dipi^er. 



Cindus americanus, Vmcu. and Sw. F. Bor. Am. vol. 11, p. 173. — AuD. B. of A. Oct. toI. II, p. 18a, pi. 137. 

 Cindus morlonii fy lownsendii, AuD. B. A. Fol. pi. 435. 

 Sydrobata mexicana, Baird, Gen. Rep. IX, 229. 



This interesting species I found in abundance on the mountain rivulets of northern California, 

 preferring the clear limpid streams, and often forsaking a locality when the water is made turbid 

 by miners washing the earth in search of gold. Alighting on the edge of the water it patiently 

 awaits the passage of its prey, uttering at intervals a low buzzing whistle which is repeated at 

 short intervals. Quite unsuspicious, it is easily approached and killed, but if wounded only, it 

 dives with great celerity, using its wings under water to propel itself forward. During the late 

 survey I met with and procured but one single specimen, on the small stream which takes its 

 rise near the summit of the Tejon Pass. 



MIMUS POLYGLOTTUS, Linn .—Common Mocking Bird. 



Orfhfus j«,lyoloUm, DeKay, N. Hist. N. Y. part I, p. 67, pi. 39, fig. 84.— Aud. B. of A. Oct. vol. II, p. 187, pi. 138. 

 Tunlus jHityrjloUus, AuD. Fol. pi. 21.— WiLS. Am. Orn. vol. II, p. 13, pi. 10, fig. 1. — Nrrr. Orn. vol. I, p. 320. 

 Mtmus polyghliua, var. cauduliis, Baibd. Gen. Rep. IX, 344. 



This bird was first observed on Posa creek, and was found abundant in the valley of Los 

 Antfelos, where they frequented the low bushes and hedges of prickly pear, still growing around 

 the fields of the abandoned missions, and forming an impenetrable barrier. The fruit of this 

 plant was at the time ripe, and the throats of several of the birds killed were tinged a deep 

 carmine from its juice. We met occasionally with this species during the second survey, under 

 Lieutenant Parke, and when passing through western Texas it proved to be one of the most 

 common birds of the country. 



MIMUS MONTANUS, Towns.— Kocky Mountain Mocking Bird. 



Orpheus motitanw, Towns. Journ. Acad. N. S. Phil. vol. VII, p. 192. — AcD. B. of A. Oct. vol. II, p. 194, pi. 139. — 



Id. Fol. pi. 3C9, fig. 1. 

 Oreoscoptes montanus, Baibd, Gen. Rep. IX, 347. 



This species is often met with in southern California, having remarked it on several occasions 

 in the environs of San Diego, and from thence to Fort Yuma. In New Mexico and Texas we 

 found it, seeing one or more individuals daily for over three hundred miles after leaving El 

 Paso. On being flushed it flies but a short distance, and generally alights on the ground, 

 running some way before it stops. When in the arid regions where the cactus abounds, the 

 ripe fruit of which affords its iavorite food, it alights on the branches of that plant, and although 

 I have closely examined the feet of several individuals, it would appear that it sufi"er8 no incon- 

 venience from the needle like points projecting from fill parts of these plants. 



