THE OOLOGIST. 



185 



Longspiir Tragedy," by Thomas S. 

 an "Exhibition of Lantern Slides," and 

 "Similarity of the Birds of the Maine 

 Roberts, was postponed until the fol- 

 lowing day. Prof. Wells C. Cook, of 

 the United States Department of Ag- 

 riculture, Washington, D. C, followed 

 with a paper on "Discontinuous Breed- 

 ing Ranges." The author cited in- 

 stances of birds found breeding in 

 the southern extremity of the south- 

 ern hemisphere while between the two 

 extended a vast area over which they 

 were not found during the breeding 

 season. He also mentioned other in- 

 stances of species having restricted 

 breeding ranges, separated by exten- 

 sive logitudinal gaps. The final speak- 

 er of the session was Abbott H. Thay- 

 er, Dublin, N.H.,who demonstrated his 

 claims regarding protective coloration 

 In animals, which, as he explained 

 and abundantly convinced his au- 

 dince, are not theories, but facts. 

 First regarding the views hitherto held 

 of the efficacy of coloration harmoniz- 

 ing with surroundings. Mr. Thayer 

 explained that theis was dependent on 

 the nature and effect of the light that 

 the creature was seen in. 



His contention was that the prevail- 

 ing light conditions have the tendency 

 to bring the upper parts into strongest 

 relief, blending into least conspicuous- 

 ness on the under parts. To counter- 

 act this tendency, Nature has colored 

 her creatures darkest above, shading 

 to lightest beneath. The speaker gave 

 a demonstration of his contention by 

 exhibiting an imitation of a leopard, 

 ground color shaded as in nature, from 

 darkest above, to lightest beneath, also 

 with spots shown, and with a back- 

 ground painted in the same color as 

 the animal. By alternately lighting 

 from above and below, the creature 

 was made to disappear, when seen in 

 the normal, top light, and to stand out 

 sharply, despite the exact similarity of 

 color to background, when seen in a 



bottom light. Secondly the speaker 

 contended that the white upper mark- 

 ings 'on many creatures, can not be 

 guiding signals for others of the same 

 species, because from the pursuing 

 creature's range of vision, these mark- 

 ings would usually come against the 

 sky-line, and therefore disappear 

 against the sky. They are, therefore, 

 of importance in reducing the crea- 

 tures' silhouette against the sky, by 

 subtracting the area of the part that 

 thus blends into the sky. Mr. Thayer 

 also gave a number of other demon- 

 strations. The title of his paper was 

 "The Principles of the Disguising Col- 

 oration of Animals." 



The opening paper of the forenoon 

 session of the final day was "The Col- 

 lection of Birds in the New York- Zoo- 

 logical Park," by C. W. Beebe, New- 

 York City. Mr. Beebe gave many in- 

 teresting experiences in connection 

 with the various experiments that he 

 has such an excellent opportunity of 

 conducting at the Zoological Park, 

 among others mentioning an experi- 

 ment with two young White-throated 

 Sparrows hatched in the park. These 

 birds were fed in the same manner 

 on the same kind of food, but one was 

 kept in a cage out in the light and 

 air, under fairly normal conditions, 

 while the other was kept indoors, in 

 a rather dark place, and subjected to 

 a moisture-laden atmosphere. 



At the first molt the two birds 

 showed no perceptible change, but 

 soon after the second molt, Mr. Beebe 

 found that the bird kept indoors had 

 become an almost uniform dusky col- 

 or, and with no trace to indicate the 

 identity of the specimen. The skins 

 of the two birds were exhibited. The 

 second paper was "A Contribution to 

 the Natural History of the English 

 Cuckoo, with a Review of the Liter- 

 ature on the Subject," by Dr. Monta- 

 gue R. Leverson, New York City. Dr. 

 Leverson corrected the erroneous 



