258 ]!ROOKLYN INSTITUTE ]\[USEUiM. SCIENCE BULLETIN 2. 6. 



An immature bird collected at Las Barrancas, August i, 1907, 

 is nearly uniform bistre brown above, the wings and tail dusky brown- 

 ish edged with the color of the back ; below, the throat and belly are 

 pale buff washed with ochraceous. Sides of upper breast brownish 

 olive almost meeting across the breast ; under tail-coverts, sides and 

 flanks buffy olive ; under wing-coverts ochraceous buff. In life the 

 eye was sepia brown; bill above black, below dusky grey; feet dusky 

 pea green. 



The White-throated Spine-tails frequent the almost impenetrable 

 thickets of thorny bushes, vines and stunted trees that spring up in 

 areas which have been cleared for cultivation and later abandoned, and 

 also in localities where the soil seems so poor as to be unable to sup- 

 port anything besides thorny bushes. 



In habits they remind one somewhat of the wrens. Their flight 

 is weak and when disturbed they only fly a few feet at a time, from 

 one thicket to another, rarely if ever mounting into the tree tops. 



The breeding season is evidently a long one, as at Caicara I have 

 found nests with fresh eggs the first of May and again in the middle 

 of August. The nests are extraordinary structures from 40 to 50 cm. 

 in length, composed of dr}', usually thorny twigs, from 5 to 15 cm. 

 in length, skillfully woven into an upright cylindrical shaped 

 mass with a long tubular entrance to the nest cavity, which occupies 

 the lower half of the cylinder. They are sometimes built within from 

 3.5 to 15 cm. of the ground among the thorns of low bushes, the foliage 

 of which completely hides the nest. Again, I have found them 1.22 m. 

 from the ground, above the tops of the surrounding buslies, not in 

 any way concealed, the body of the nest resting in the forks of a low 

 tree and the entrance tube supported along the top of one of the limbs. 

 The twigs at the top of the body of the nest are laid longitudinally so 

 as to form a sort of thatched roof over all. The eggs are a uniform 

 pale greenish in color ; and three constitute a full set. 



A nest, and three fresh eggs taken at Caicara May 9th, was built 

 only about 15 cm. above the ground in a low dwarfed tree, whbse 

 branches bristled with short, thin and exceedingly sharp thorns. It 

 was completely concealed from above and on the sides by foliage. 

 The nest is constructed entirely of small, dry, and for the most part 

 thorny sticks, from 5 to 12 cm. in length. But, in spite. of the thorns, 

 and the consequent irregular shape of the twigs employed, they are 

 laid together and interwoven with such skill that only very small 



