FAMILY PARULIDAE 



331 



basis of egg-white data and morphology. The parulid affinities of Zele- 

 donia were confirmed by Raikow's (Bull. Carnegie Mus. Nat. Hist., 7, 

 1978, p. 28) dissections of the musculature, which also suggest that 

 Zeledonia may be more nearly related to Basil eutcrus. As the name 

 "Wrenthrush," formerly applied to this bird, is now seen to be inap- 

 propriate, the name "Zeledonia" has been used in its place. 



Figure 26. — Zeledonia, Zeledonia, Zeledonia coronata. 



Until James Hunt studied it in Costa Rica during 1968 (Auk, 1971, 

 pp. 1-20), little was known of the biology of Zeledonia except its 

 whistled call and that it was a very secretive inhabitant of dense under- 

 growth in the humid herb layer of high mountains and in tangles and 

 vines on trunks and lower limbs directly above it, where it hops and 

 flicks its wings, but very rarely flies. The Zeledonia's commonest call 

 is a "thin, high-pitched whistle, usually with a slight rising inflection," 

 transcribed by Ridgely as a very piercing, sibilant pseee. The song, 

 which Hunt first heard on March 19, is a sequence of phrases like 

 sseee-del-deet with emphasis on the last syllables. 



Hunt found a nest under construction on March 25. It was situated 

 in a cavity in a vertical mossy bank of a small stream. The nest, finished 

 on March 31, was a domed structure with an entrance on the side, 

 made of mosses with a few small leaves and twigs and lined with fine 

 dead plant material, including grass, mosses, and decaying leaves. The 

 first egg was laid on April 8. It and a second, laid 2 days later, were 



