ANATIN^ — THE DUCKS - ERISMATURA. 103 



to have been of the same style and pattern, and nothing is said of any other mate- 

 rial than down being used in building them. The number of eggs varied from five 

 to eight ; but the latter number was found in only a single instance. 



This Duck was seen breeding near Fort Kesolution by Mr. Kennicott in June, 

 18G0, and on the Yukon River both by him and Mr. Lockhart. It was found near 

 Fort Simpson by Mr. B. R. Ross and Mr. McDonald ; near Fort Rae by Mr. L. Clarke ; 

 and at La Pierre House by Mr. J. Flett. 



We have no data in reference to any peculiarly distinctive habits of the so- 

 called P. Trowhridg'd that would enable us to state whether these exhibit anything 

 of a specific character. The individuals upon which this supposed species was 

 founded were taken by Lieutenants Trowbridge and Williamson at San Diego in 

 the winter of 1853. Two other specimens have since been obtained by Mr. Bischoff 

 at Sitka. 



Dr. Cooper writes that although he was constantly on the lookout for Ducks of this 

 species while on the southern coast of California, he never succeeded in finding 

 one. If any do occur, he thinks that they must have come as stragglers from the 

 coast of Asia. 



Eggs of the Surf Duck obtained on the Arctic coast east of Anderson River by 

 Mr. MacFarlane (Smithsonian Institution, No. 95G6) are of a uniform ivory-white 

 color, with a slight pinkish tinge, ranging from 2.25 to 2.30 inches in length, and 

 averaging about 1.60 in breadth. 



Genus ERISMATURA, Bonaparte. 



Oxyura, BoNAP. Synop. 1828, 390 (type, Anas rubida, Wils.); nee Oxyurus, Sw. 1827. 



Erismatura, Bonap. Saggio Distr. Met. 1832, 143 (same type). 



Gyvinura, Nutt. Man. II. 1834, 426 (same type). 



Undina, Gould, Birds Eur. V. 1836, pi. 383 (type, Anas mersa). 



Cerconedes, Wagl. Isis, 1832, 282 (same type). 



BytJwnessa, Glogeh, Handb. 1842, 472 (same type). 



Char. Bill about as long as the head (much longer than the tarsus), very broad, widened 

 toward the end, elevated at the base, the nostrils very small, and situated very near the cubnen ; 



"h^r---^^ 



E. rubida. 



maxillary unguis very small, narrow, and linear, the terminal half bent abruptly downward and 

 backward, so as to be invisible from above ; tail more than half as long as the wings, much gradu- 



