ced the same interesting
fact--that in the breeding season each form selects a special precinct,
into which the other form does not intrude. They perhaps put up some
kind of trespass sign. These observations have all but convinced me that
_S. magna_ and _S. neglecta_ are distinct species, and avoid getting
mixed up in their family affairs.

Nor is that all. While both forms dwell on the vast prairies of
Oklahoma, Kansas, and Nebraska, yet, as you travel eastward, the western
larks gradually diminish in number until at length they entirely
disappear; whereas, if you journey westward, the precise opposite
occurs. I have never heard _neglecta_ east of the Missouri River,[4] nor
_magna_ on the plains of Colorado. Therefore the conclusion is almost
forced upon the observer that there are structural and organic
differences between the two forms.

[4] He sometimes ventures, though sparingly, as far east as Illinois
and Wisconsin; still my statement is true--I have never heard the
western lark even in the bottoms and meadows of the broad valley
east of the Missouri River, while, one spring morning, I did hear
one of these birds fluting in the top of a cottonwood tree in my
yard on the high western bluff of that stream.

After the foregoing deductions had been reached, the writer bethought
him of consulting Ridgway's Manual on the subject, and was gratified to
find his views corroborated by a footnote answering to an asterisk
affixed to the name of the western lark:

"Without much doubt a distinct species. The occurrence of both _S.
neglecta_ and _S. magna_ together in many portions of the
Mississippi Valley, each in its typical style (the ranges of the two
overlapping, in fact, for a distance of several hundred miles),
taken together with the excessive rarity of intermediate specimens
and the universally attested radical difference in their notes, are
facts wholly incompatible with the theory of their being merely
geographical races of the same species."

This has been a long _excursus_, and we must get back to our jaunt on
the plain. While I was engaged in watching the birds already named, my
ear was greeted by a loud, clear, bell-like call; and, on looking in the
direction from which it came, I observed a bird hovering over a ploughed
field not far away, and then descending with graceful, poising flight to
the ground. It proved to be the Arkansas flycatcher, a large