Todd-Carriker : Birds of Santa Marta Region, Colombia. 143 



The. question here raised by the junior author is answered, at least 

 in part, by a set of two beautifully marked eggs received from Mr. 

 Smith, collected at Taganga on July 12, and accompanied by a pencil 

 sketch of the cave in which they were found. The eggs were laid on 

 the bare rock, in accordance with the usual habits of this species. 



Family ACCIPITRID^. Hawks. 



26. Chondrohierax uncinatus uncinatus (Temminck). 

 Leptodon uncinatus Allen, Bull. Am. Mus. Nat. Hist, XIII, 1900, 131 

 (Bonda). 



Fifteen specimens: Bonda, Mamatoco, and Chirua. 



The variations in plumage in this species are most perplexing, not 

 being susceptible of interpretation on any one basis. Mr. Ridgway 

 long ago. {Bulletin U. S. Geological and Geographical Survey of the 

 Territories, II, No. 2, 1876, 156) described the plumage of the several 

 stages of the bird in its progress from youth to maturity, all of which 

 stages are represented in our series. The youngest individuals appear 

 to be those with brown upper parts, barred under surface, and many- 

 barred tails. As the bird grows older the upper surface changes to 

 slaty gray, the barring of the under parts becomes less pronounced, 

 and the bars on the tail are reduced in number and correspondingly 

 increased in width. In very old birds the entire plumage is uniform 

 slaty, including the wings, while the tail shows only two light bars, 

 a broad one about the middle of the feathers and a narrow one at their 

 tips. We have one specimen (No. 8,650, Bonda,. April 10) showing 

 the moult from the brown-backed to the slaty-backed dress, and thus 

 far the sequence of plumages seems natural and orderly enough, al- 

 though it is impossible to say how long the full change requires. But 

 the matter is complicated by melanism, as Mr. Ridgway has shown, and 

 also, as we believe, by albinism and erythrism. There are two speci- 

 mens of our series (one from the interior of Colombia), both appar- 

 ently young birds (judging from their tails), which are white below, 

 varied only with a few dusky and rufescent bars. On the other hand, 

 there are four specimens with tails precisely like that of the subadult 

 stage above described, but which show no sign whatever of slaty above, 

 and are otherwise indistinguishable from younger birds. One of the 

 four (a female) is further remarkable for its large size (wing, 313; 

 tail, 193) and heavily barred and strongly rufescent under parts. It is 



