212 



THE OOLOGIST 



apex in any one of the specimens. 

 Size 20 X 17 mm., one of the eggs be- 

 ing perceptibly smaller than the other 

 three, measuring 19 x 15.5 mm. The 

 figure of the egg of this species given 

 us Reed has almost a subellipsoidal 

 form, while the marketing is about the 

 same. 



Fig. 2. 2. Passerella iliaca megar- 

 hyncha. 



Thick-billed Fox Sparrow. 

 Passerella megarhynchus 

 Baird, Rep. Expl. & Surv. 

 R. R. Pac, IX., 1858, 925. 

 (Fort Tejon, California.). 

 Range. — Mountains of Cal- 

 ifornia. Breeds in Transi- 

 tion Zone on both slopes of 

 the Sierra Nevada from 

 Mt. Shasta to Mt. Whit- 

 ney; winters in south- 

 western California; casual 

 in Marin County. (A. O. U. 

 Check-List, p. 277.) 

 Here we have a fine nest and three 

 eggs of this species, collected by Mr. 

 A. M. Ingersoll at Butte Meadows, 

 Butte County. California, on the 22d of 

 June. 1914. (Set mark 2333.) When 

 taken, incubation was advanced 

 the nesting site being "about two feet 

 above rocks in a matted down clump 

 of deer brush. A nest with three 

 young was found at a distance of less 

 than 200 feet, on same date." 



Neither Dr. Coues nor Chester Reed 

 gives any description whatever of the 

 nest and eggs of this subspecies of 

 Fox Sparrow. 



The exterior of the nest at hand is 

 composed of a great quantity of coarse 

 twigs and sticks of various plants, 

 shrubs and vines, mixed with one or 

 two pieces of some dark-brown, coarse 

 bark of a vine. They are loosely 

 woven together, in an elongo-ovate 

 outline when viewed from above (Fig. 

 2), the twigs extending much further 



in one direction than in the opposite 

 one, while the opposite sides are about 

 flush with the inner part of the nest 

 at its external limits. . This inner por- 

 tion is composed of rather soft, brown- 

 ish grass and of some fine vegetable 

 fibers and roots, the whole weave be- 

 ing somewhat firm and compact, the 

 finest material having been used inter- 

 nally, and becomes gradually coarser 

 as we proceed toward the coarse sticks 

 of the external part. 



Internally, this nest has a depth of 

 some two centimeters, with an aver- 

 age width of five centimeters. Rough- 

 ly calculated, its longest external 

 diameter equals about twenty centi- 

 meters, and the transverse one, meas- 

 ured across the middle of the nest, 

 about ten centimeters. Its concavity 

 is nearly hemispherical in form, while 

 the rough outer portion appears to 

 have been built to accomodate the 

 finer part, or to sustain it in the cleft 

 in which the birds built the structure 

 as a whole. In other words, the outer 

 part is a mere platform of coarse 

 twigs and sticks, upon which the true 

 nest has been skillfully modeled and 

 incorporated with, as shown in the re- 

 production of my photograph of the 

 specimen. 



The three eggs composing this 

 clutch have each as ground color a 

 shade of rather dull olive blue — more 

 on the blue than on the olive. They 

 are densely speckled all over with 

 minute spots and dashes, and witli 

 other very fine markings of a rusty 

 brown shade, being decidedly coarser 

 and denser at the butt than any other 

 part of the egg. On one of these eggs 

 the markings are exceptionally fine, to 

 become appreciably coarser in the two 

 remaining specimens. On the average 

 they have a measurement of 2.2 x 1.7 

 cms., and they veyr scarcely at all in 

 their size and form for the clutch. 



