BIRDS OF THE CAMBRIDGE REGION. 49 



long, narrow and perfectly rectangular pits, dug, as I am assured by my vener- 

 able neighbor, Mr. Royal Stimpson, about the middle of the last century to 

 obtain the rich meadow peat which was spread over certain of the farm lands 

 along Vassall Lane. Before I came to know these pools, however, nature had 

 done much to obliterate the traces of their artificial character, for most of them 

 had become choked with aquatic vegetation and bordered by tall reeds, cattail 

 flags, sweet gale, briers (^Rosa nitida), button-bushes, alders, viburnums and 

 other moisture-loving plants. They were visited at one or another season by 

 Pied-billed Grel)es, Black Ducks, Green winged and Blue-winged Teal, Wood 

 Ducks, Bitterns, Least Bitterns, Green Herons, Night Herons, Rails, Gallinules 

 and Mud-hens. Interspersed among them, and also surrounded by bushes, 

 were grassy openings where Wilson's Snipe occurred numerously at times, and 

 where Carolina Rails and Swamp Sparrows nested. Virginia Rails bred 

 throughout the thickets, which were also tenanted in summer by very many 

 Red-winged Blackbirds, Song Sparrows, Yellow Warblers and Maryland Yel- 

 low-throats. At the eastern edge of the swamp a few pairs of Long-billed 

 Marsh Wrens had established a colony as early as 1868. 



Muskrat Pond. 



Muskrat Pond lay on the opposite side of Concord Avenue, near the foot 

 of Vassall Lane and less than one hundred yards from the eastern end of Cam- 

 bridge Nook. It was a pretty little pool, not unlike some of those in the Brick- 

 yard Swamp, but larger than any of them and very much deeper. As its name 

 indicates, it abounded in muskrats, who built their conical houses all about its 

 quaking, treacherous margin. It also attracted a few water-fowl, especially Teal 

 and Mud-hens. Here it was that I shot my first Duck — a Pintail — in 1863 

 or 1864, and here Ruthven Deane and I found several Florida Gallinules — two 

 of which we killed — in the autumn of 1868. There was a wide stretch of 

 boggy meadow just to the eastward, where Snipe and Yellow-legs alighted at 

 times, and where Carolina Rails were accustomed to breed. Both pond and 

 meadow have long since disappeared, and in their place yawns a deep and un- 

 sightly clay-pit. 



The Glacialis or Artificial. 



The little sheet of water formerly known as the Glacialis, but now oftener 

 called the Artificial (the word pond is seldom or never used with either term), 

 lies j ust across Alewife Brook from the Maple Swamp. Concord Avenue passes 



