NORTHERN SMALL-BILLED WATERTHRUSH 483 



have little data on the summer song, however, and cannot give aver- 

 age dates for the time of cessation." 



Francis H. Allen tells me that he has recorded the song as '■'■wheet 

 wJieet chip chip chip wheedleyou, and as wheet wheet chip chip chip 

 chip chip'-u^ the final w rather faint. A call or alarm note is a sharp, 

 metallic or perhaps 'stony' chip^ thinner than that of the ovenbird, but 

 carrying well." In 1912, in Newfoundland, I recorded the song as 

 chip chip chip chip chitter chitterew. 



Gerald Thayer wrote to Dr. Chapman (1907) : 



At its best the song of this species is not quite so fine, perhaps, as that of 

 Seiurus motadlla — it is very different, and has a rare grace and vigor of its 

 own. Like the Oven-bird the Northern Water-Thrush makes up for a great 

 general regularity of singing by an occasional wide lapse into variation. Its 

 flight-song, a performance relatively far less common than the Oven-bird's (?), 

 seems to be nearly changeless. It is like the common perch song, but quicker and 

 longer, and "framed" in a hurried jumble of half-call-half -song notes ; — the whole 

 delivered as the bird dashes horizontally through or barely above the woods. 

 Most notable among the few important variations of its perch-song I have heard 

 was a long, liquid strain seemingly made up of at least three united repetitions 

 of the regular utterances, going unusually fast, in a thinner tone, and inter- 

 sprinkled with sharp notes of "chippering," unlike the common call-notes. The 

 typical perch-song itself is hard to describe in words. A ringing, bubbling 

 warble, swift and emphatic, made up of two parts, barely divided, the second 

 lower-toned and diminuendo. 



Dr. Sutton (1928) recognizes the song as expressed by the human 

 words, '"'Hurry ^ hurry ^ hurry, pretty, pretty, pretty.'''' 



Albert R. Brand (1938) gives for the song of this species a range 

 of from 2,000 to 3,850 vibrations per second, with an approximate 

 mean of 2,925, the lowest frequency, or the lowest pitch, that he re- 

 corded in any of the other wood warblers, except the yellow-breasted 

 chat. 



Field murks. — The bird with which the northern waterthrush is 

 most likely to be confused is its congener, the Louisiana waterthrush ; 

 the former has a buffy line over the eye and sulphur-yellow under 

 parts, streaked with black almost up to the chin; the latter has a 

 more conspicuous pure white stripe over the eye, a much whiter 

 throat, and white underparts, streaked less conspicuously with olive- 

 brown ; the latter also has a larger bill. The ovenbird has no stripe 

 over the eye. 



Enemies.— Dr. Friedmann (1929) says that the waterthrush is 

 "rarely victimized" by the cowbird ; probably the latter has difficulty 

 in finding its nest, as only four observers have reported cases of 

 victimization. 



Harold S. Peters (1936) reports one louse, Menacanthus sp., and 

 two bird-flies, Ortdthoica conflusnta Say and Ornithomyia anchineuria 

 Speiser, as external parasites on the northern waterthrush. 



