A Tragedy in Nature 151 



again when we wanted to photograph them. Their nests were neatly 

 made of dry and green reeds, closely woven together, often arched over 

 above, and looking very pretty with the large, pure white eggs. Some- 

 times they, too, were imposed upon by the careless Redheads. 



Had time and strength not been exhausted, we might have studied 

 the many other interesting birds we saw, — the Mallards, Pintails, and 

 Blue-wing Teals nesting in the grassy borders of the slough, the Long- 

 billed Marsh Wrens chattering in the flags, and the Short-eared Owls 

 and Marsh Hawks on the surrounding prairies; but even the long 

 North Dakota day was drawing to a close, and we reluctantly turned 

 away from the fascinating and almost bewildering scenes of this 

 wonderful locality. 



A Tragedy in Nature 



BY WILLIAM BREWSTER 



AT Lancaster, Massachusetts, on May 24 last, I noticed a swarm of 

 Bank Swallows flying about over the river near a low bank in which 

 were a great number of their nesting holes. It was a newly-estab- 

 lished colony, for no birds had bred on this particular stretch of river in 1901 

 or 1902. Visiting the place again on the afternoon of June 19, I counted 

 one hundred and eight holes but, greatly to my surprise, there were no 

 birds in sight. At length, however, a single pair appeared and one of them 

 repeatedly entered a hole (always the same hole) with food for its young. 

 Feeling sure that something must be wrong I approached the bank and 

 examined it attentively. For a distance of about eight feet back from the 

 water's edge the surface of the ground was sandy or gravelly and sloped 

 only very gently upward. Above this for a distance of perhaps six feet 

 (measured along the surface) the slope was at an average angle of about 

 forty-five degrees and the soil, like that of the vertical bank still higher up, 

 pure, fine, hard-packed sand. The vertical portion averaged about two 

 feet in height and was slightly overhung in places by the loamy turf of the 

 pasture land above. All the Swallows' holes were, of course, in the verti- 

 cal face of the bank, most of them being nearer the top than the bottom 

 and a good many close under the projecting sod. A glance satisfied me 

 that the village boys had not molested them, for they showed no traces of 

 enlargement. What, then, could have banished the birds from so appar- 

 ently safe and congenial a nesting place .'' As I was speculating on this 

 point I noticed some scratches on the face of the bank immediately below 

 one of the holes. On examining the other holes I found that only one 

 (that which I had seen the bird enter) was without these tell-tale marks. 

 Xhey resembled deep pin-scratches and extended from the entrances of the 



