1918 Dwight, A New Species of Loon. 197 



From among the specimens of the Striped Diver which I have collected 

 I will only cite the adults: 



1. ? 9 Near Amu — Daryi, Feb. 2, 1907. 



2. 9 Near Kok — Boowak, Nov. 4, 1907. 



3. cT Kasalinsk, April 16, 1908. 



4. d" Lake Chushka — Kool (near Turkestan City) June 10, 1908. 



5. 9 Lake Chushka — Kool (near Turkestan City) June 10, 1908 



6. d> At the source of the River Tar — Toogi, Dec. 22, 1909. 



7. ? d" Nijni — Tcherchik, Winter 1909-10. 



8. ? 9 Boowaki, on the lower heights of Koorataou, Spring 1911. 



9. d" Joolek, Baiga — Kum, March 28, 1911. 



The divergences are the following : The gray color of the crown and the 

 back of the neck of the Turkestan bird is lighter, though not quite as light 

 as in Urinator pacificus Lawr. The explanation of this should not be sought 

 for in moulting, as one might be led to expect by specimen No. 1, which is 

 in process of changing its winter plumage for its summer one. In speci- 

 mens Nos. 2, 6, and 7, we can notice very clearly that the parts above- 

 mentioned are also lighter. The white horizontal bars on the shoulders 

 and on the back are in most cases wider, even comparing the small 

 Turkestan birds with the large Pskovkoi and St. Petersburg types. Also 

 in most cases the white spots on the wings are larger. The front part of the 

 neck seems to be darker and its purple sheen less developed. 



In the greater number of cases our birds are smaller and their beaks are 

 shorter. These two observations were already made by Mr. P. P. Suschkin 

 (Birds of the Ufinskoi Region. — Birds of the Middle Kirgiz Steppes.) in 

 the cases of Divers from the Ural and Turkestan regions. In my specimens 

 the length of the wings and culmen are as follows: 



(In typical U. arcticus, the length of the wing varies between 12,15" and 

 13,2", and the culmen between 2,5 and 2,85. In U. pacificus the wing is 

 11,2"- 12,25" and the culmen 2"-2,35".) 



The extremity of the beak in the Turkestan Diver, is shorter and higher 



