Capl. Sabine's Memoir on the Birds of Greenland, cjc. 551 



23. Lauus Sabini. Forked-tailed Gull. 



A full description of this bird having been already presented to 

 the Society*, it is unnecessary to repeat the account. 



Mr. 'reniminck informs nie that he has seen this bird in the 

 Museum at Vienna, where it was proposed to call it Larus colla- 

 ris, but that it has not been described by the ornithologists of that 

 capital, or by any author whatsoever before the Memoir above 

 referred to was presented to the Society. The specimen, he thinks, 

 was obtained from Professor Giesecke ; but the bird is not to be 

 found in a MS. list of Greenland birds in his own hand-writing, 

 with the sight of which I have been favoured by Mr. Bullock, nor 

 is any other Gull there mentioned with which it could possibly 

 have been confounded. 



24. Lestkis Parasiticus. 



Catharacta Parasitica. Fabr. 103. 



Mature. Larus Parasiticus. Gmel. ii. 601. Lath. Lid. Orn. ii. 819- Faini. 

 Suec. 55. Milll. no. Id6. Te/HW. 512.— Arctic Gull. Br. Zool. ii. 179. Ant. Zool. ii. 

 530. Lath. Syn. vi. 389- Mont. Dict.Si .Si/;?^.— Catharacta Parasitica. Bruit, no. 127- 



In brown Plumage. Catharacta Coprotheres. Briin. no. 128. 



Immature. Lestris depidatus. Temm.5\5. — Larus Crepidatus. Gmel- ii. 602. 

 Lath. Ind. Orn. ii. 819. — Black-toed Gull. Br. Zool. ii. 178. Arct. Zool. ii. 531. 

 Lath. Syn. vi. 387. Supp. 263. Mont. Diet. S; Supp.—Laius Cepphus. MM. no. 168. 

 — Catharacta Cepphus. Briin. no. 126. 



I have followed the example of Temminck in removing this 

 with the other dark-coloured Gulls from Larus and giving them 

 the generic appellation of Lestris. Much inaccuracy as well as 

 difference of opinion has existed respecting not only the imma- 

 ture, but the mature birds of this species. The immature bird 

 has been described as a distinct species. Montagu was the first 

 author who had a doubt of the correctness of this arrangement, but 

 he erred in considering the young bird as a variety only. It has been 



* See page 520 of this volume. 



called 



