Dr. Heermann afterwards, being at Comanche Springs in Texas, had his attention attracted by the new note of a bird unfamiliar to him. It was found, after some observation, to proceed from this species. He describes it as rising with a tremulous motion of its wings some twenty feet or more, and then descending again, in the same manner, to within a few yards of the spot whence it started, and as accompanying its entire flight with a lengthened and pleasing song. The country in that neighborhood is very barren, covered with low stunted bushes, in which the bird takes refuge on being alarmed, gliding rapidly through the grass and shrubbery, and very adroitly and effectually evading its pursuer. He observed them during four or five days of the journey of his party, and after that saw no more of them. They seemed, at the time, to be migrating, though their continued and oft-repeated song also showed that they were not far from readiness for the duties of incubation. The _Peucæa cassini_ is said, by Mr. Sumichrast, to be a resident species in the valley of Orizaba, in the State of Vera Cruz, Mexico, and to be generally distributed throughout the temperate region of that district. It is very probable, however, that he has in view the Mexican race of _P. æstivalis_ (var. _botterii_), and not the present species. Mr. J. A. Allen, who considers this bird only a western form of _P. æstivalis_, mentions (Am. Naturalist, May, 1872) finding it quite frequently near the streams in Western Kansas, where its sweetly modulated song greets the ear with the first break of dawn, and is again heard at night till the last trace of twilight has disappeared. Mr. Allen also states, in a letter, that this bird was “tolerably common along the streams near Fort Hays, but very retiring, singing mostly after nightfall and before sunrise, during the morning twilight. When singing, it had the habit of rising into the air. I shot three one morning thus singing, when it was so dark I could not find the birds. The one I obtained does not differ appreciably from specimens from Mr. Cassin’s collection, labelled by him _Peucæa cassini_, collected in Texas.” Mr. Ridgway regards this record of the manners of this bird, while singing, as indicating a specific difference from _P. æstivalis_. The latter, in Southern Illinois, has never been heard by him to sing at night, or in the morning, nor even on the wing; but in broad midday, in the hottest days of June, July, and August, he often heard them singing vigorously and sweetly, as they perched upon a fence or a dead tree in a field, exactly after the manner of our common _Spizella pusilla_.