Taverxer — On Yellow-Breasted Chat in Mich. 17 



30. Penthestes atricapillus septentrionalis. Long-tailed Chica- 

 dee. — Pei'haps the birds seen really belong to the Columbian "isl- 

 and" of atricapillus proper, but they appear to me lighter in tone, 

 with more of white edging on wing and tail. 



31. Penthestes gambeli. Mountain Chickadee. — Active members 

 of the Amalgamated Push. 



32. Regulus satrapa olivaceus. Golden-crowned Kinglet. — Not so 

 common as on Puget Sound. Only once seen, on a densely thick- 

 eted hillside. 



33. Merula migratoria propinqua. Western Robin. — Several lin- 

 gering about the orchards and shade trees of Cannon Hill. 



34. Sialia mexicana occidental is. Western Bluebird. — Still com- 

 mon locally; a dozen seen Nov. 20th. These birds are undoubtedly 

 intergrades and possibly deserve to be classed as S. m. bairdi. 



Seattle, Wash. 



THE YELLOW-BRE.\STED CHAT IX AHCHIGAN. 



p. A. TAVERNER. 



Southern jNIichigan* marks the extreme northern hmit of 

 the range of the Yellow-breasted Chat in the Middle West. 

 They can hardly be regarded in the state as common or reg- 

 ular- visitors, except locally. They must be viewed as in- 

 trusive forms from the Carolinian Fauna to the south of us 

 that have, for the past decade or so, been extending their range 

 northward. In the past, they have appeared here occasionally 

 under pectiliar and, as yet, unknown conditions, persisting for 

 a while, and then vanishing more or less conipletelv for a 

 greater or less i>eriod of time. 



The causes of these intrusions and disappearances are still 

 beyond explanation. They seem to come and go according 

 to no law, rule or set of conditions. That they are but 

 accidental and the result of chance no scientific man will 

 for a moment admit ; but the complexity of the conditions 

 renders the solution very difficult indeed. In many cases, such 

 investigation involves an exhaustive study of the conditions 

 prevalent over the winter ranges of the individuals in question ; 

 and until we have positive data regarding where the different 

 individuals of the various northern races spend their winters 

 we cannot hope for any great success along these lines. It 

 mav be well to call attention to the fact that these occtirrences 



