104 Birds of Colorado 



eggs. He believed that a second brood was usual, and 

 that the first eggs were laid about May 20th. On another 

 occasion he watched a large number of these birds on 

 a lake near Boulder. Some of the birds had paired 

 and kept near the shore where they were busy feeding, 

 but the larger number were swimming about in the centre 

 of the lake. These he subsequently watched performing 

 a series of aerial evolutions under the leadership of one 

 bird — up, around and zigzagging to and fro across the 

 lake. He believed that these birds were preparing to 

 go further north. 



The eggs, usually four in number, are rather pyriform 

 in shape ; they are greenish or olive-bro^vn, rather thickly 

 spotted and blotched with sepia or blackish-broA\Ti, and 

 measure I'lO x 80. 



Family RECURVIROSTRID^. 



This small family comprises the Avocets and Stilts, 

 characterized by their long legs and bills, which latter 

 are either straight or up-turned ; tarsus without scutes, 

 covered wdth reticulate scales ; toes three or four, semi- 

 palmate or nearly fully webbed. 



Genus RECURVIROSTRA. 



Bill long and pointed, much longer than the head, both mandibles 

 flattened and up-curvod towards the tips ; legs long, the tarsus about 

 twice the length of the middle too and covered with reticulated scales 

 all round ; hind toe small but clawed, front toes about half -webbed. 



A cosmopolitan genus of four species, only one of which is North 

 American. 



American Avocet. Recurvirostra americana. 



A.O.U. Checklist no 225— Colorado Records— Aiken 72, p. 209 ; 

 Coues 74, p. 4G0 ; Henshaw 75, p. 448 ; Drew 81, p. 18 ; Morrison 89, 

 p. 167 ; Goss 91, p. 152 ; Cooke 97, pp. 18, 64, 199 ; Dille 03, 

 p. 74 ; Henderson 03, p. 234 ; 09, p. 227 ; Markman hi, p. 156 ; 

 Warren 09, p. 14. 



