THE OOLOGISr. 



183 



tography, notably birds on the wing, 

 probably, of any living photographer 

 and nature student, and the series of 

 slides shown on this occasion were a 

 wonderful revelation of his success 

 along this line. Tne possibilities of 

 bringing out the principles of wing 

 movement in flight were strongly indi- 

 cated, though Mr. Finlay regards his 

 work as only a step in this direction. 

 The third paper of this session was 

 "The Status of Certain Species and 

 Subspecies of North American Birds," 

 by J. Dwight, Jr., of New York City. 

 In this paper. Dr. Dwight, following a 

 line of reasoning which he adopted 

 several years ago, regarding the pro- 

 cedure of the American Ornithologists' 

 Union in the matter of nomeclature, 

 argued against the hair-splitting meth- 

 ods of differentiation that has led to 

 such confusion in the case of certain 

 geograi hical forms. 



The case was discussed from the op- 

 posite si:Ie by Mr. Oberholser, impar- 

 tially by Dr. Allen, and very strongly 

 in favor of a more simple and less 

 complicated method, by Mr. D. G. El- 

 liott. The last paper of this session 

 was "Wild-fowl Nurseries of North- 

 west Canada," by Herbert K. Job, 

 Kent, Conn. Mr. Job is one of the pio- 

 neer bird photographers, and his 

 work is among the best. His slides 

 illustrated the home life of the water- 

 fowl, which are still to be found in 

 great colonies in this wild northern 

 country. 



After the dinner of that evening, 

 the members returned to the Museum 

 for an informal reception, at which 

 there was a demonstration of a new 

 projection apparatus. This apparatus, 

 not only projects slides, but a magni- 

 fied and beautifully clear colored re- 

 flection of any small object, introduced 

 into the objective is shown in color 

 on the screen. , 



The first paper of the morning ses- 

 sion of the second day was "Andrae 



Hesselius, Pioneer Delaware Ornithol- 

 ogist," by C. J. Pennock, Kennett 

 Square, Pa. This paper dwelt prin- 

 cipally with extracts from the note- 

 books of this Swedish missionary, 

 whose observations were made some 

 two hundred years ago. At that time 

 ornithological observations were few, 

 and those included in these notes were 

 extremely interesting, and couched as 

 they were, in the quaint style of the 

 time, often very amusing. Following 

 this paper came one by Witmer Stone, 

 of Philadelphia, Pa., on "The Proba- 

 bility of Error in Bird Migration Rec- 

 ords." Mr. Stone spoke of the con- 

 ditions that tend to admit error in the 

 records as gathered by single isolated 

 observers, and recorded the methods 

 he has adopted, of grouping observers 

 in parties of three or four, who prac- 

 tically cover the same ground, thus 

 affording the opportunity of checking 

 and averaging the observations of oth- 

 ers. Mr. Stone followed this paper by 

 one on "Some Observations on the Ap- 

 plicability of the Mutation Theory to 

 Birds." The discussion of this paper 

 which followed, by Dr. Allen and oth- 

 ers showed a disinclination to admit 

 the applicability of this theory, to 

 birds. Henry Oldys. of Washington, 

 D. C, followed with a discussion of 

 "The Song of the Hermit Thrush." Mr. 

 Oldys has for some time devoted him- 

 self to the study of bird song, and gave 

 an interesting account of his exper- 

 ience in securing an opportunity to 

 study the Hermit's song, of his im- 

 pressions regarding it, and its compar- 

 ison to th song of the Wood Thrush. 

 Mr. Oldys gave some pleasing imita- 

 tions of a variety of songs of each of 

 these two species, and concluded by 

 i-endering a little song, the words of 

 which he had composed, to the air he 

 had recorded from the most accom- 

 plished of the Hermit songsters to 

 whom he had listened. 



Mr. Chapman concluded the fore- 



