116 BULLETIN: MUSEUM OF COMPAKATIVE ZOrJLOGY. 



the mountains south of La Paz, especially on the Sierra de la Laguna, where it 

 ranges from the highest elevations down to the lower limits of the oaks among 

 the foothills. It also occurs — at least sparingly and locally at certain seasons 

 — in the low arid country near the coast, for Mr. Frazar took a male at La Paz 

 on February 11, and saw upward of a dozen at San Jose del Cabo in Septem- 

 ber. At the latter place, Mr. Belding found it " common in orchards " about 

 the last of April, 1882. Among the mountains it shows a marked preference 

 for canons, especially such as have pools or small streams of water. Mr. Bel- 

 ding says that "in winter" it is " found only in mountain canons," but Mr. 

 Frazar's experience was exactly the reverse of this, for during his winter visit 

 to the Sierra de la Laguna (November 27-December 2), the '* whole top of the 

 cold, sleety mountain was alive with Xantus's Hummers, which seemed to be 

 attracted there by an abundant shrub covered with dry yellow blossoms, whereas 

 in May and June they were confined quite closely to the canons." The truth 

 of the matter probably is that their movements, like those of most other mem- 

 bers of this family, are dependent largely on the presence or absence, at any 

 given locality or season, of the flowers on which they feed. 



A nest found at San Jos6 del Rancho, on July 28, was placed at the extremity 

 of a slender, drooping oak twig, about eight feet above the ground. One 

 side is built against and around the main stem (here only .12 inches in diam- 

 eter), and the bottom rests securely on a terminal fork, from the ends of which 

 hang a number of dry, bleached oak leaves, apparently of the previous year's 

 growth. The chief, if not only, material composing the walls of this nest con- 

 sists of small, woolly leaves of a pale sage-green color, intermixed with reddish- 

 brown, catkin-shaped objects, which appear to be made up of numerous minute 

 seed vessels attached in double, triple, or quadruple rows or clusters to stems 

 an inch or more in length. The entire outer surface of the nest is wrapped 

 with a net-work of spider-web silk so fine as to be well-nigh invisible but suffi- 

 ciently strong and tautly drawn to give the walls a firm, smooth outline. The 

 interior is not lined save at the bottom, which is furnished with a soft bed of 

 whitish down, evidently that of some bird. This nest measures externally 

 1.60 inches in diameter by 1.65 in depth; internally, .73 inches in diameter 

 by .50 in depth. 



Tyrannus vociferans Swains. 



Cassin's Kingbird. 



Tyrannus vociferans Beldikg, Proc. U. S. Nat. Mus., V. 1883, 541 (Cape Begion); 

 VI. 1883, ."48 (Laguna). Bryant, Proc. Calif. Acad. Sci., 2d ser., II. 1889, 

 290 (Cape Region). 



Mr. Frazar found Cassin's Kingbirds abundant at La Paz in February, and 

 early March, when they seemed to be passing northward. They were numerous 

 again, on the return migration, during the last week of August and first ten 

 days of September, at San Jose del Cabo, but rare in December (18-25) at 



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