56 ARKIV FÖR ZOOLOGI. BAND 13. N:0 4. 



100. Saltator albicollis isthmicus (Sclater). 



Saltator albicollis isthmicus Bångs, Auk. XVIII, 1901, 32 (San Miguel) — 

 RiDGWAY, Birds North Midclle Am. I, 1901, 669 (San Miguel) — Thayer 

 and Bångs, Bull. Mus. Comp. Zoöl. XLVI, 1905, 159 (San Miguel; 

 Saboga). 



Saltator striatipectus isthmicus v. Berlefscii, Ber. V. Int. Orn.-Kongr. 1910, 

 1118 (San Miguel). 



BovALLius' Collection: \ ^, I ^, Viveros, April 8 and 11. 



RiDGWAY, who examined fourteen specimens from San 

 Miguel in the collection of Messrs. Bångs, says (op. cit. page 

 670, foot-note), «These birds show decided color differences- 

 from an equally large series from the mainland, the under 

 parts having much less of the olive-yellowish wash acros& 

 chest and along sides, and the streaks grayer. The upper 

 parts are also grayer, especially anteriorly. » Mr. Ridgway, 

 however, had no specimens of corresponding date (end of 

 April to beginning of May) from the Isthmus and leaves the 

 question undecided, whether the differences are seasonal or 

 otherwise. 



In the collection of the State Museum there are no other 

 skins of S. a. isthmicus, so I am unable to make any compa- 

 rison. 



The measurements are as follows: 



ö", Viveros L: wing 91; tail 94; exposed culmen 18; tar- 

 sus 23. 



$, Viveros L: wing 88,5; tail 85,5; exposed culmen 18,5; 

 tarsus 21,5. 



Tryckt den 16 juli 1920. 



Uppsala 1920. Almqvist & Wiksells Boktr.-A.-B. 



