402 NESTS AND EGGS OF 



egg a beautiful rich salmon-colored hue. Ten eggs selected out of 

 fifteen sets give the following measurements : .86 x .62, .89 x .62, .93 x 

 .-63, .90 x .60, .94 x .67, .96 x .67, .95 x .66, .94 x .69, .95 x .67, .98 x .69. 

 The average size is .97 x .65. Their general shape is oblong-oval. 



714. Campylorhynchus affinis XANTUS [57.] 



Sti Lucas Cactus Wren. 



Hab. Southern portion of Lower California. 



The habits, nesting and eggs of this species are identical with 

 those of the last. 



715. Salpinctes obsoletus (SAY) [58.] 



Rock Wren. 



Hab. Arid regions of Western United States from the Great Plains to the Pacific, south through 

 Mexico to Northern Central America. 



This is a more or less common species in the dry, rocky regions 

 of Western United States. Mr. Scott says that in the Catalina Moun- 

 tains of Arizona they begin to breed about the middle of March ; six 

 or eight young are the common inmates of the nest, and two broods 

 are reared. Mr. Emerson found this species to be quite common on 

 the Farallon Islands, and it is the only land bird which is resident. 

 They were found all over the South Farallon, building in suitable 

 crevices a nest of Farallon weed, lining it with chicken feathers and 

 .hair shed from the island mule. 



The nest is usually built in a rift of rocks, or on the ground be- 

 -neath some shelving rock. It is composed of a mass of material, very 

 miscellaneous in character, sometimes a single substance, but a variety 

 of materials are more generally used, such as sticks, bark-strips, weeds, 

 grasses, moss, hair, wool, etc. A curious habit of the Rock Wren is 

 that of paving the ground about the entrance of the nest with pebbles, 

 or bits of rock and glass. On the Farallons small pieces of coal, mus- 

 sel shells, and small bones of sea-birds and rabbits are used for this 

 purpose. Mr. Fred Corey, of Santa Paula, California, informs me 

 that he found a nest with four eggs of this bird under the rafters of a 

 house. 



Five and six eggs constitute an average set, and seven, eight, or 

 nine are sometimes deposited. Mr. Emerson found one nest with ten 

 eggs, two of which were fresh and the others in various stages of incu- 

 bation. The eggs are pure glossy white, finely and sparsely speckled 

 with reddish-brown, chiefly at the larger end. Mr. Norris has two 

 sets taken on the Farallons, June 16 and 23, 1886 ; they contain six 

 and eight eggs respectively and measure . 70x^6, .73 x .56, -7IX.56, 

 .,69 x .56, .69 x .56 ; .74 x .59, .72 x .57, .74 x .58, .76 x .58, .75 x .58, .75 x 

 ..58, .76 x .59, .75 x .59. Another set collected in Rio Grande county, 



