290 BULLETIN 133, UNITED STATES NATIONAL MUSEUM 



a dense mat of tangled branches 3 meters above the stream, attracted 

 by a squeak, and bobbed about in a wrenlike manner. The bill, in 

 life, was black; base of mandible light neutral gra}^; tarsus fuscous 

 black ; toes smoke gray ; iris carob brown. 



The bird measures as follows: Wing, 52; tail, 44; exposed culmen, 

 12.5; tarsus, 18.5 mm. 



RHINOCRYPTA LANCEOLATA (Is. Geoffroy and d'Orbigny) 



RMnomvQ, lanceolata, Isidore Geoffeoy and cI'Orbigny, Mag. Zool., 1832, 

 cl. 2, pi. 3. (Cai-meu and Salina d' Andres Paz, Rio Negro.*"*) 



In the valley of the Rio Negro, below General E,oca, Rio Negro, 

 the present species was common from November 23 to December 3, 

 1920; a female was taken November 23 and males on November 23, 

 27, and December 3. The birds were encountered usually in rather 

 heavy growths of open brush that clothed the arid flood plain of 

 the stream, and few seemed to range inland through the still drier, 

 gravelly hills that formed the northern border of the valley. 

 Though common, E. lanceolata was shy, and was seen or secured 

 only at the expense of considerable effort. The birds normally ran 

 about on the ground with crest erect and tail cocked at an angle 

 above the back. As I traversed their haunts I was greeted by a low 

 vrut prut prut^ or a musical tulloch, from the brush on either hand, 

 and occasionally had a glimpse of one of the elusive birds as it 

 darted across some little opening. Occasionally, when safe behind 

 a protective screen of low weeds or a drooping branch, one stopped 

 to peer back at me, or less frequently with a running jump one 

 sprang into the branches of a bush and clambered up for a 

 better outlook. It is doubtful if Rh'mocrypta has occasion to fly a 

 hundred meters in the course of a month, a circumstance that has 

 given rise to the appropriate local name of corre corre que no vuela. 

 The slight breast muscles were pale in color, indicating a poor blood 

 supply, and loose and flabby in substance in contract to the strong, 

 heavy leg muscles. The heavy operculum that overhung either nos- 

 tril was movable, and was so developed that it may serve as a pro- 

 tective device that aids breathing during the constant heavy wind- 

 storms of these regions, during which the loose earth forms a dense 

 dust cloud in the air. On December 3 I found a nest placed more 

 than a meter from the ground amid heavy branches in a dense, 

 thorny bush. The somewhat bulky structure was an untidy affair 

 made of weed stems, bits of bark, and grasses, lined with finer 

 material. The top was covered in an arch, and the entrance was a 

 large irregular opening in one side. The nest contained two white 

 eggs and two of the spotted eggs of the glossy cowbird {Molothrus 



83 d'Orbigny, Voy. Am^r. M6rid., Ois., vol. 4, pt. 3, 1835-44, p. 195. 



