1096 U.S. NATIONAL MUSEUM BULLETIN 23 7 iaut 2 



extinct and Bryant's notes provide the best account of the avifauna 

 as it once existed. 



Bryant found the j uncos inhabiting primarily the pine and cypress 

 groves, remaining for the most part on the ground among fallen 

 trees, or in the lower branches. He reported that the juncos were 

 paired soon after the beginning of the year and were setting by Jan. 

 26, 1886, despite almost continuous cold fogs and winds. No court- 

 ship behavior has been described. 



Bryant collected a male Jan. 2, 1886, Avith "testes large"; males 

 taken Jan. 26 and Feb. 4, 1886 had "testes very large." Of two adult 

 males and one adult female that we collected biu-ing the second week 

 of June 1953, one male had enlarged testes (6 by 6 millimeters) and 

 the others did not have enlarged gonads. These data and the records 

 of nests and young cited below indicate that insularis has a long 

 breeding season, beginning in January and ending in June. 



Nesting. — Palmer (in Ridgway, 1876) reports a nest in a rock 

 crevice, and Bryant (1887) states that the ground beneath a fallen pine 

 was most often used as a nesting place. He describes one nest as being 

 "in a depression, flush with the surface of the ground, and so carefully 

 hidden beneath a covering of brush that it was found with difficulty 



* * *." Another nest Bryant described was 6 feet above ground in 

 a narrow cleft between two conjoined pine trees. It was constructed 

 of "a few pieces of bark-moss, light-colored dry grass blades, and a 

 tail feather of a petrel, all siurounding a quantity of grass blades, lined 

 within with goat hair. It measures externally about 120 mm. in 

 diameter by 80 mm. in height, with a receptacle 60 mm. in diameter 

 and only 28 mm. in depth." 



Brown and Marsden (in Thayer and Bangs, 1908) describe a nest 

 found in May or June of 1906 "placed on the lower branch of a pine 



* * * bulky and made mostly of dried grass stems." 



Eggs. — W. E. Bryant (1887) describes a clutch of three fresh eggs 

 taken on Mar. 10, 1886, as follows: "In color the eggs are a pale 

 greenish white, marked with fine dots of reddish brown clustered 

 around the larger end. They measm-e 19.5 x 15; 20 x 15.5; 20 x 16 

 millimeters." 



Bryant believed that these eggs were a second clutch as he noted 

 young birds already present in other nests at that date. H. B. 

 Kaeding (1905) found both fresh eggs and fledged young on Mar. 22, 

 1903. Palmer (in Ridgway, 1887a) reports a nest with eggs on Apr. 

 12, 1875. Bryant, and BroAvn and Marsden mention nests containing 

 four young, and it seems likely that three or foiu* eggs is the usual 

 clutch. 



According to W. G. F. Harris (MS.) the eggs of the Guadalupe junco 

 are very pale greenish white, speckled and spotted with reddish browns 



