THE AMKinCAN OnMTIlOLOin^TS' rXTON 



483 



ornithologT on a hroadt'i- scale than lias 

 hitherto been possibh'. 



On every side teclniical. thcdi'dical. 

 and practical problems await solution. 

 The problem of the siibsjiecies only be- 

 gins with tlic naiiiiiii:' of an (ibscui-cly 

 marked foi-m. and the moi'c dilliciilt 

 questions n\' \\\v hird's disti'ihuti(Hi. life 

 history, and relation to other forms still 

 remain to be worked out. In spite of 

 the progress made in recent years eei-- 

 tain mysteries of bird migration still 

 confront ns. Where is the winter home 

 of the chimney swift or the breeding 

 ground of the blue goose? These fa- 

 miliar (|uesti(uis cannot I'emain unan- 

 swered much longer. As for other ques- 

 tions of migration, bird banding prom- 

 ises to throw much light on the routes 

 traversed by migrants, and aviation on 

 the height and speed at which birds 

 travel. How shall we learn more of the 



extinct Mrds n\' America now known 

 only hy a few rragiiieiitai'v bones, and 

 how shall We |n'e\cii1 I'l'diii lii'conung 

 extinct othei' \alual)le s])ecies now 

 threatened wit h extermination ? These 

 and olhei' proMems ranging from the 

 jturely theoretical to the severely prac- 

 tical await solution l)y competent inves- 

 tigators. 



I*]ven amid the distractions of war, 

 ])lans are being made for broadening 

 the scope of the American Ornitholo- 

 gists' Union so as to make the organiza- 

 tion international in fact and enable it 

 to assume its share of the larger under- 

 takings in the world's work. To each 

 and all who are interested in birds the 

 Union extends a cordial invitation to 

 join in the advancement of ornithology 

 and the advancement of members in 

 ornithological science. 



Figure from ;i rcitnt luimlitT of JItr Auk. oUiiial orKim of tlu' Aiiicrican Ornithologists' Union, illus- 

 trating the study of life histories of birds in the field. This nest of the bay-breasted varbler {Dcndroica 

 castanea) was photographed by Messrs. P. B. Philipp and B. S. Bowdish in June in northern Xew 

 Brunswick. Collectors of the American Museum of Natural History have found this warbler in the 

 mountains of Colombia between the middle of December and March 10. The route by which the bird 

 reaches the tropics and return.s again the next spring is one of the problems of migration as yet un- 

 solved. Since the bay-breast occurs neither in Me.xico nor Florida, it is sujtposed to fiy across the broad 

 expanse of the Gulf of Mexico in the course of its long journeys from its breeding grounds to its winter 

 home and back again 



