Birds of Pennsylvania. 15 



by forty feet, immediately over a shoal of grass, and took their stand 

 on the shore in a hut of brush, each having three guns well loaded 

 with large shot. The Ducks, which were Hying up and down the 

 river in great extremity, soon crowded to this place, so that the whole 

 open space was not only covered with them, but vast numbers stood 

 on the ice around it. They had three rounds, firing both at once, and 

 picked up eighty-eight Canvas-backs, and might have collected more, 

 had they been able to get to the extremity of the ice after the wounded 

 ones. In the severe winter of 1779-80, the grass on the roots of which 

 these birds feed was almost wholly destroyed in James river. In the 

 month of January, the wind continued to blow from W.N.W. for twenty- 

 one days, which caused such low tides in the river that the grass froze 

 to the ice everywhere, and a thaw coming on suddenly, the whole was 

 raised by the roots and carried off by the freshet. The next winter a 

 few of these Ducks were seen, but they soon went away again, and 

 for many years after they continued to be scarce ; and even to the 

 present day, in the opinion of my informant, have never been so 

 plenty as before." 



Food. 



Audubon, writing of the food of the Canvas-back, says : '' It varies 

 according to the season and locality. The plant Vallisneria., on which 

 it is said to feed when on the head- waters of the Chesapeake, is not 

 found equally abundant in other parts, and even there is at times so 

 reduced in quantity that this Duck, and several other species which 

 are equally fond of it, are obliged to have recourse to fishes, tadpoles, 

 water-lizards, leeches, snails and mollusca, as well as such seeds as 

 they can meet with, all of which have been in greater or less quan- 

 tity found in their stomachs." 



My examinations of four of these Ducks, which were killed at 

 Havre-de-Grace, showed only vegetable substances, which I judged 

 to be remains of Vallisnei'ia. 



Wilson asserts that the Canvas-backs when feeding on the Vallis- 

 neria eat only the roots, and, on the other hand, the Red-heads feed 

 on the stems of this plant. 



Genus CHARITONETTA. Stejneger. 

 153. Charitonetta albeola (Linn.). 



Buffle-head. 



Description. 



Male. — Bill blue; head and neck antei'iorly dark colored; the region in front of 

 the eye and on the sides of the collar behind rich green ; this color shading into 

 purplish on the upper and under surfaces of the head ; a broad patch on each side of 

 the head from the posterior border of the eye, and meeting its fellow on the nape, 

 the lower neck all round, under parts generally, wing coverts (except the lesser), 



