58 NOin'II AMKRICAN BIRDS. 



iiccustoiiKHl to the society ol' tlie niillei'S. Tlioy liad jn-oviously niisiHl aii- 

 Dtluii" bvood that season. 



Tlie saiiK! oliscrsaiit naturalist, some time al'terwards, in l\Iay, found tlie 

 nest ol" anotiior pair, a lew niik's north oi' Santa Clara. This was built near 

 the loot of a niill-dani, resting on a sliijlit le(lu,o under an over]ian<,an<^' rock, 

 from which water was continually drojtping. It wa.s, in shiipe, like an oven, 

 with a small doorway, and it was Imilt externally of green ino.ss, which, being 

 still living, ])reventeil tlie easy discovery of the nest. It was lined witli soft 

 grass, and containetl young. 



These l)irds are found .singly or in pairs, and never more than two together. 

 They are never found near still water, and frequent only wild mountain- 

 streams, ca.scades, eddies, and swift currents. 



According to ^Ir. Dall's ob.servations in Ala.ska, the species is e.s.seiitially 

 solitary. He obtained .several specimens in .lanuary, February, and March, 

 always near some open, unfrozen s])ots in the Nulato IviAcr. It was only 

 found in the most retired spots, and almost invarialily alone. Wiien dis- 

 turbed, it would dive into the water, even in midwinter. 



Mr. Eidgway describes the I)i]ii)er as remarkably (|\iick, as well as odd, in 

 its movements, — whether walking in the shallow bed of the stream, or 

 .standing on a stone along the edge, contimially tilting u]) and down, now 

 chattering as it Hies rapidly along the stream, again alighting into the water, 

 in whicli it wades with the greatest facility. Its liigiit is remarkably swift 

 and well sustained, and in manner is very unusual, the bird ]iro]iellin/ itself 

 by a ra])id buzzing of the wings, following in its ilight every undulation in 

 the course oi' the stream into whicli it drops suddenly. Its song is d(>scribed 

 as remarkably sweet ami lively, in modulation re.senjbling somewhat that of 

 tli(! ffiir/)<ir/i)/iir/iiis riifiis, l)ut less j)owerl'ul, though sweeter in effect. 



Dr. K. lialdamus, of Halle, who jxisse.sses sjiecimens of the eggs of this 

 s])ccies, describes them as pure white in color, oval in shajie, and hardly 

 distinguishalde from those of the European 6'. ni/nc/lrns. 



A nest of this bird obtained by Mr. .1. Stevenson, of Ilayden's Expedition, 

 in lierthoud's Pass, Colorado, is a hemisphere of very uniform contour built 

 on a rock, on the edge of a stream. Externally it was eompo.sed of gri'en 

 moss, in a living state ; within is a strong, compactly built apartment, 

 arched over, and su]tportccl by twigs, with a cup-like deju'cssion at the bot- 

 tom, hemispherical and eompo.sed of roots and twigs firndy bound together. 

 The structure is 7 inches in height externally, and has a diameter of lOJ 

 inches at tlu; ba.se. Within, the cavity has a depth of (1 inches; the 

 entrance, which is on one side, is M^ in breadth by 2\ in height. The eggs 

 were tliice in number, uniform, dull white, and unspotted. They measure 

 1.('4 inches liy .70. They have an elongated oval shape, and are much 

 pointed at one end. 



