274 



A. BROOKER KLUGH. 



The following Austral birds breed on the peninsula red- 

 headed woodpecker, Baltimore oriole, townee, indigo bunting, 

 migrant shrike, brown thrasher, catbird, prairie warbler (see 

 Saunders '06, Klugh '09, '10), wood thrush and bluebird, while 

 of the Canadian birds mentioned above only the white-throated 

 sparrow, Blackburnian warbler, myrtle warbler and hermit 

 thrush breed, the two latter being rare as summer residents. 



The above data shows conclusively that the Bruce Peninsula 

 is in the Transition Zone. 



o Georgian 

 ----Bay: 



- - C> 



Lake 

 Huron. 



It is of course obviously impossible to adequately represent 

 the boundaries between life-zones and faunal areas by a sharp 

 line, since the change from one zone or area to another is' gradual 

 and not abrupt. But our lines should be drawn through the 

 region where a comparatively few miles north or south shows 

 an appreciable change in the biota. In the case of the line 

 between the Canadian and Transition Zones in Ontario this is 

 certainly not true if the line is drawn through central Ontario, 

 nor is it true if it touches Georgian Bay low down. It is not 

 until we reach the mouth of the Shawanaga River that we have 

 a clearly Canadian fauna and flora to the north and a Transition 

 biota to the south. That the line should be drawn as indicated 

 on the accompanying map is shown by the data given by Fleming 

 ('oi) and Wright ('20) as well as by my data. 



