80 A. F. CEOSSMAN — NOTES ON BIEDS 



The two narrow light bars on the wings of the bird showed up 

 very plainly while it was flying. Street told me that it usually 

 occurred at the Kesei^voirs during the spring and autumn migration. 

 On April 7th, and again on April 19th, Street saw one of these 

 birds. The greenshank has been recorded on two former occasions, 

 namely, in 1880 near Watford, and in 1885 at the Eeservoirs, 

 when two were shot. 



CiiELEW [Numenius arquaUis). — One of these birds was seen at 

 the Reservoirs on Api'il 29th, and on August 16th Street saw 

 fifteen of them at Wilstone Reservoir. On December 21st he 

 observed sixteen of these birds, which is the largest number he had 

 ever seen together at the Reservoirs. The curlew has been recorded 

 on several occasions in Hertfordshire. 



Black Tern {Eydrochelidon nigra). — One of these birds was 

 seen at the Reservoirs by Street on April 17th, and on the 20th 

 I saw one at Marsworth Reservoir. On May 6th Street observed 

 a large party of common terns at Wilstone Reservoir, and amongst 

 them were a few black terns. On August 7th he saw three more, 

 and on August 17th I noticed another. Several of these birds 

 have been obtained in Hertfordshire, and it was thought at one 

 time that some pairs had stayed to nest at the Reservoirs, but the 

 fact has never been proved. This is another bird which formerly 

 bred commonly in the Fen districts, but which has now been 

 banished chiefly by drainage. 



Common Teen {Sterna Jluviatilis). — The common tern occurred 

 on several occasions in 1895 at the Reservoirs, and on one occasion 

 (May 6th) Street saw nearly fifty of them in company with some 

 black terns. This bird, which occurs nearly every year at Tring, 

 has been seen on several occasions at Elstree Reservoir, and in 

 1881 some were killed in the neighbourhood of Royston. 



Lesser Teen {Sterna minuta). — On October 10th Street saw 

 three of these birds at the Reservoirs. In 1882 some of these 

 birds were obtained at Royston; while in April, 1886, two were 

 obtained at the Reservoirs by the Hon. Walter Rothschild, and one 

 was also obtained there in 1885. 



Common Gull {Larus camis). — On August 17th I observed what 

 I took to be a bird of this species at the Reservoirs, and on 

 November 25th Street saw several of them there. It has occurred 

 frequently in Hertfordshire. 



Black-backed Gulls. — On June 14th, and again on ITovember 3rd 

 and December 17th, Street saw some black-backed gulls at the 

 Reservoirs, but he did not mention to what species they belonged. 

 The great black-backed gull has occurred on a few occasions in this 

 county, but the lesser black-backed gull has only been procured 

 once. 



Kittiwake {Jiissa tridactyla). — On Tilay 19th I saw a kittiwake 

 flying over Kerkhamsted Common. In January, 1885, two were 

 shot at the l^escrvoirs, and in February in the same year one was 

 picked up at London Colney, near St. Albans. These are the only 

 recorded occurrences in Hertfordshire. 



