156 U.S. NATIONAL MUSEUM BULLETIN 22 3 



birds. In the normal daylight periods at Cliicago, where the studies 

 were carried out, these birds did not assume nuptial plumage for 

 nearly 2 years, but in suitably controlled experiments they were in- 

 duced to acquire breeding plumage during their first year of life by 

 being subjected to daily light periods of 16 hours. Steganura proved 

 less resistant to the effect of increased light than did Vidua and 

 Eupledes. In a subsequent report, RoUo (1941, p. 162) noted that 

 paradise widow birds assumed nuptial plumage in a 12-hour period, 

 but went into eclipse plumage in both a 10- and a 16-hour period. In 

 other words, a daily light period above or below the optimum actually 

 retarded the appearance of breeding plumage. Autopsy revealed a 

 correlation between the state of the gonads and the onset of nuptial 

 feathering, so it becomes wholly proper to utilize breeding plumage as 

 an indication of gonadal activity in this bird, even though the duration 

 of the plumage is greater than the actual breeding season. 



As stated in the opening paragraphs of our account of the paradise 

 widow bird, all the recognized forms are considered conspecific. The 

 differences between the races are presented immediately after the 

 description of the plumages. 



Adult male in breeding plumage: Forehead, lores, crown, most 

 of occiput, cheeks, auriculars, chin, and throat Black with faint pur- 

 plish-blue gloss. Broad nuchal collar from posterior part of occiput 

 and liind neck extending to sides of neck posterior to sides of head 

 varying from shining golden Light Yellow Orange to pale Mars Yellow 

 to Orange-Buff in some races (»S'. p. paradisaea, obtusa, orientalis, kadu- 

 gliensis), and deep Orange-Buff to bright Sanford's Brown in others 

 (S. p. aucupum, inter jecta, togoensis). Back, rump, upper wmg coverts, 

 upper tail coverts, long mner secondaries, and long median rectrices 

 Black with slight velvety purplish-blue sheen. Other secondaries, 

 primaries, and lateral rectrices Fuscous, narrowly edged with white 

 when first acquired, but these edgings and tips quicldy worn off. 

 Primaries internally edged to varying extent with whitish. Black of 

 throat extending posteriorly in a V on middle of breast. Rest of breast 

 bright Sanford's Brown to rufous Chestnut, paling somewhat laterally 

 and posteriorly. Abdomen, sides, and flanks bright Ochraceous-Buff 

 to Pale Ochraceous Buff. Tuft of white feathers on flanks on either 

 side. Abdomen paling on midventral area to buffer whitish. Thighs 

 buffy whitish. Under tail-coverts dull blackish tipped vAxh. white. 

 Iris dark brown. Bill black. Feet dark brown. Wings 76-83 (79) 

 mm. Long rectrices 245-345 (300) mm. Shorter rectrices 60-65 (63) 

 mm. Culmen 11-12 (11.7) mm. Tarsus 16-17.5 (17) mm. Length 

 and terminal breadth of long tail feathers vary greatly in different 

 subspecies. 



