FAUNAL AREAS. 15 
Careful scrutiny of Dr. Wheaton’s work will make appar- 
ent to any one that there has been a very perceptible move- 
ment of many species northward or north-eastward during 
the last two decades. Several species known then to breed 
near the lake shore clearly do not breed there now, or if 
at all very rarely. Several species which did not reach the 
lake shore then are regular breeders there now. Some spe- 
cies which were confined to the southern border of the state 
twenty years ago have now reached the central counties, 
or pushed even farther north-eastward. Bewick Wren, at 
least, has invaded the state from the south-west. There is 
some indication of an invasion of the Blue Grosbeak and 
Nonpareil soon. In winter, we in the north now have Rob- 
ins and Bluebirds with us in small numbers, where seven 
years ago none remained. The temperature is not chang- 
ing, but the birds are gradually developing into hardier an- 
imals. 
The species involved in this north-eastward movement 
may be mentioned. Of the warblers: the Prothonotary, 
Worm-eating, Golden-winged, Chestnut-sided, Magnolia, 
Kentucky, and the Hooded. Besides these the Summer 
Tanager; White-eyed Vireo; Pine Siskin; Lark Sparrow ; 
Dickcissel ; Cardinal; Carolina Wren; Bewick Wren; Tur- 
key Vulture ; and Wilson Snipe. These are the species most 
affected. It is more than likely that the whole bird host is 
gradually shifting northward as the weaker ones perish, leav- 
ing only the hardier individuals to occupy the arena of daily 
strife for existence. 
From WHENCE Birps Have Come Into Onto. 
Birds seem to have appeared upon the earth during the 
lower Jurassic or possibly even during the upper Triassic 
times in the world’s history. No fossil birds of these times 
have been found in Ohio, yet it is not impossible that such 
occurred in the region now named Ohio. However that 
may be, it is certainly true that the great ice invasion from 
the north, marking the close of the Tertiary Period and the 
