WATER BIRDS. 49 



Club, Vol. IV, 1903, p. 94). Dr. Gibbs informs us that W. H. Collins 

 of Detroit in a letter which he has, says "Two specimens taken on Detroit 

 River, fall of 1876, and now in collection of Dr. Jasper, Columbus, Ohio. 

 One taken in October, 1883, in dark plumage." 



We have recently (Nov. 2, 1905) examined a nice specimen of this species 

 in the Barron collection at Niles. It is an immature bird in a plumage 

 intermediate between the light and dark phase and the middle tail-feathers 

 but an inch longer than the rest. Although without any label it was 

 probably taken in that vicinity. 



In habits this bird does not differ much from the preceding, but is 

 decidedly more common on the Atlantic coast, and is probably more a bird 

 of the coast than of the open sea. It nests far north of our Hmits, laying 

 eggs similar to those of the Pomarine Jaeger and averaging 2.30 by 1.64 

 inches. 



TECHNICAL DESCRIPTION. 



Adult: Most of the head, neck and under parts wliite or yellowish white, the top of 

 head and the lores brown; the rest of the upper parts dark slate. Occasionally an adult 

 is found which is brownish black or very dark slate all over. Yoimg birds (full grown) 

 are mostly brownish, variously streaked and barred with whitish or buff, the streaking 

 most noticeable on head and neck, the barring on back, breast and belly. 



Length, 15.50 to 21 inches; wing, 11. 80 to 13.50; longest tail-feathers 4.90 to 6.25; culmen, 

 1.15 to 1.40. 



Family 5. LARID^.— Gulls and Terns. 



KEY TO SPECIES. 



A. Outer tail-feathers longest (tail more or less forked). — C, CC, CCC. 

 C. Large; wing more than 13 inches. — D, DD. 



D. Largest; bill thick; tail forked less than two inches, hind head not 



crested. — Caspian Tern. No. 19. 

 DD. Smaller; bill more slender; tail forked 3 inches or more; hind 

 head crested. ^ — Royal Tern. No. 20. 

 CC. Medium; wing 9 to 12 inches.— E, EE. 



E. Outer tail-feathers much narrowed at tip. — F, FF, FFF. 



F. Outer web of outer tail-feather darker than inner web. — G, GO. 

 G. Bill red with black tip (in summer). — Common Tern. No. 



22. 

 GG. Bill all red (in summer). — Arctic Tern. No. 23. 

 FF. Inner web of outer tail-feather darker than outer wel); bill 



red, black-tipped. — Forster's Tern. No. 21. 

 FFF. Both webs of outer tail-feather white; breast wliite or 

 rose-tinted. — Roseate Tern. (Appendix.) 

 EE. Outer tail-feathers not narrowed at tip. — Sabine's Gull. No. 

 18. 

 CCC. Small; wing less than 9 inches.— H, HH. 



H. Back and upper sui'face of wings and tail slate-color or dark grav; 



bill black.— Black Tern. No. 25. 

 HH. Back and upper surface of wings pale peai'l-gray; bill yellow, 

 black-tipped. — Least Tern. No. 24. 

 7 



