'909.] THE CAYUGA LAKE BASIN, N. Y. 433 



In all other portions of the basin they are fairly common. At En- 

 field on May 5, 1907, A. A. Allen found a nest containing five eggs. 



248 (486a). Corvus corax principalis Ridgvvay. Northern raven. 

 " Formerly not uncommon at the north end of the basin. The 



last reported was one, seen by Foster Parker in 1880, pursued by a 

 number of crows." (Eaton). 



249 (488). Corvus brachyrhynchos C. L. Brehm. Crow. 

 Common permanent resident. Nests containing eggs are most 



commonly found from April 10 to 20. In 1903 a nest containing 

 eggs was found on April 3. The latest record of nest and eggs is 

 May 16, 1900. 



68. Family Icterid^, The Blackbirds and Orioles. 



250 (494). Dolichonyx oryzivorus (Linnaeus). Bobolink. 

 Common summer resident. The average date of spring arrival 



is May 4, the earliest, April 30, 1900. By July 10 they are gathered 

 in large flocks in the marshes where they remain through August 

 and the first of September, at about the middle of which they depart 

 for the south. 



251 (49s). Molothrus ater (Boddaert). Cowbird. 



Abundant summer resident. The average date of spring arrival 

 is March 28, the earliest, March 14, 1899. Eggs are found from 

 May 5 to June 15. The maximum period of egg-laying is the last 

 half of May. The phoebe, the vireos, redstart and yellow warbler 

 are the most common victims of the cowbird's parasitic habits, 



252 (498). Agelaius phoeniceus (Linnaeus). Red-winged blackbird. 

 Common summer resident and found regularly in small numbers 



in the marshes during winter. Migration begins about March 10. 

 The earliest record is a large flock of males in full song, seen Feb- 

 ruary 22, 1902. The earliest record of nesting is May 12, 1906. 

 The most active breeding period is from the middle of May to the 

 first of June. Young are on the wing by June 5. During the first 

 two weeks of July this species collects in large flocks in the marshes 

 where they remain until the last of November. Flocks containing 

 hundreds are seen migrating all through November. So far as they 

 have been observed at Ithaca they follow the inlet valley towards the 

 south. 



