SENNETT'S OLIVE-BACKED WARBLER 151 



the eggs to rest upon. A firmer and more secure nest is seldom seen, although 

 so easily made. I imagine a day would complete one, and certainly but little 

 time need be wasted in selecting a site, for thousands of orchids stand out on the 

 partially dead branches on trees with little foliage. That they build also in the 

 hanging trusses of Spanish moss, so abundant everywhere, is true, the young 

 before referred to being found in a nest in one. 



There are two nests of Sennett's warbler in the Thayer collection in 

 Cambridge. One of these was taken for F. B. Armstrong in Tamau- 

 lipas, Mexico, on July 5, 1911, and held three eggs. It is described 

 as a "nest of hair in bunch of growing moss hanging from limb of 

 cypress tree in river bottom," 8 feet up; it is built right into the 

 TiUandsia and is made almost wholly of black and white cattle hair. 

 The other, with a set of four eggs, was taken by James Johnson near 

 Saltillo, Mexico, on May 27, 1906. It is described by the collector as 

 "dug and hollowed in a bunch of pipestem mosses." It is a compact 

 little nest made of very fine rootlets, very fine grasses, shreds of the 

 brown inner bark of the palmetto or palm, and some weed blossoms ; 

 it is lined with finer shreds, a little plant down, and a few feathers. 

 Externally it measures 2^/2 inches in diameter and 2 inches in height ; 

 the inside diameter is about II/2 inches; and the depth of the cup 

 about 1^ inches. 



Eggs. — Either 3 or 4 eggs seem to constitute the full set, as far as 

 we now know, for Sennett's warbler. The 7 eggs in the Thayer collec- 

 tion vary from ovate to short ovate, and have only a slight lustre. 

 They are white or creamy white and are speckled and spotted with 

 shades of "wood brown," "cinnamon-brown," or "Brussels brown," 

 with underlying spots of "pale brownish drab." On some eggs the 

 markings run to much darker browns, such as "auburn" and "chestnut," 

 and on these the drab spottings are frequently lacking. Usually a 

 loose wreath is formed where the spots are concentrated at the large 

 end, but occasionally they are distributed nearly evenly over the entire 

 surface. The measurements of 36 eggs average 16.3 by 12.2 milli- 

 meters ; the eggs showing the four extremes measure 19.0 by 13.7 and 

 15.0 by 11.3 millimeters (Harris) . 



Plumages. — Young Sennett's warblers that I have examined are 

 uniform grayish olive above, inclining to olive-green on the back; 

 the black lores and cheeks are lacking; the median wing coverts are 

 narrowly tipped with whitish, and the greater coverts more broadly 

 so; the chin is pale yellow; the chest and upper breast are shaded 

 with pale gray and centrally tinged yellowish; the abdomen is dull 

 white; and the sides and flanks are shaded with pale olive-grayish. 

 I have not seen enough material to trace subsequent molts and plum- 

 ages, which doubtless parallel those of the parula warbler. 



Food. — ^^Ve have no definite information about the food of Sen- 

 nett's warbler, but Clarence F. Smith has sent me the following note : 



