XANTUS'S HUMMINGBIRD 447 



"This was found by Chester Lamb on a 'thorny bush overhanging 

 a creek' in a wooded arroyo at Copalito, northeastern Sinaloa, July 

 29, 1936. The situ was the crotch of a dead twig 3 feet up from 

 the ground at the extremity of a branch of the bush. The bulk of 

 the nest is composed of the whitish cotton from the pod of the palo- 

 blanco tree. The body of the structure is completely and tightly 

 bound together on the entire external portion with very fine webbing, 

 which may have been obtained from a spiderweb but looks sur- 

 prisingly like the fine threads of the cotton itself. If so, they have 

 been very carefully pulled out and each one worked separately into 

 the nest. Three small dead twigs are attached to the external part, 

 but the chief decoration is a very beautiful 'pale glaucous-green' 

 lichen. I have not seen this particular lichen used elsewhere, and 

 I am sure it is not the oak lichen, commonly used by the white-eared 

 hummingbird. The interior of the nest has no lining other than the 

 cotton itself, but there are four lichens well inside of the margin of 

 the nest. The characteristic feature of the structure, which differ- 

 entiates it from the nest of most other species I have seen in north- 

 western Mexico, is the use of the fine tendrils of cotton or cobwebs 

 to swathe the external part of it." 



HYLOCHARIS XANTUSI (Lawrence) 

 XANTUS'S HUMMINGBIRD 



HABITS 



The type specimen of this hummingbird, a female now in the 

 United States National Museum, was taken in 1859 near Cape San 

 Lucas, Baja California, by John Xantus and was named in his honor. 

 Its center of abundance is in the vicinity of the Cape, but it ranges 

 northward to about the twenty-ninth parallel of latitude, where it 

 becomes rare. 



William Brewster (1902) says: 



This Hummingbird is peculiar to Lower California, but it is not strictly con- 

 lined to the Cape Region, for Mr. Frazar found it common at a point about 

 one hundred and fifty miles north of La Paz among the mountains opposite 

 Carmen Island in latitude 26°, and Mr. Bryant has traced its extension still 

 farther northward to about latitude 29°. It seems to be most abundant, how- 

 ever, in 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 Jos^ del 

 Cabo in September. 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. Belding says that "in winter" it is "found only in mountain 

 canons," but Mr. Frazar's experience was exactly the reverse of this, for dur- 



