176 Kopman, Bird Distribution. [April 



unusually plentiful. Here, however, Parula and Hooded Warblers 

 were, if anything, commoner than before, while the two Vireos 

 were present in great abundance. It was in this neighborhood, 

 that the Ovenbirds were seen. There was another species whose 

 presence, chiefly in the open, evidenced that the time for a general 

 passage of transients was ripe. This was the Indigo Bunting. 

 While this species breeds in southeastern Louisiana, it is never 

 common in most localities except during migration; individuals 

 in all stages of plumage, including many old males, were observed. 

 Tree Swallows had reached the height of their spring abundance 

 also, and it is of interest to note that the history of their spring 

 movements reflect very closely many stages of the general vernal 

 advance of birds in southern Louisiana. Though this trip proved 

 so unproductive as an opportunity for the observation of mid- 

 spring transients, the largest number of species yet observed under 

 somewhat similar conditions, and at the same time and place, 

 include only the Black-and-white and Cerulean Warblers and the 

 Redstart as exclusively transient species. 



After the middle of April, the conspicuous occurrence of tran- 

 sients is by no means so rare. As explained by the writer in a 

 previous paper, the presence of transients at this season usually 

 occurs with fresher weather. Yet even on these occasions, I have 

 never found any of the transients decidedly and uniformly com- 

 mon except Yellow Warblers, Catbirds, and Gray-cheeked, Olive- 

 backed, and Wilson's Thrushes. At various times I have seen 

 scattering Baltimore Orioles, Rose-breasted Grosbeaks, Scarlet 

 Tanagers, and Black-and-white, Blue-winged, Golden-winged, 

 Tennessee, Magnolia, Cerulean, Chestnut-sided, Bay-breasted, 

 Blackburnian, and Black-throated Green Warblers, and Red- 

 starts, but never the pervading hosts of these species observed at 

 the height of spring in the north. When occurring, these species 

 seldom if ever resort to the ordinary woodland, but usually to the 

 edge of the woods, and to groves and thickets in the midst of culti- 

 vation. The extreme refinement of such creatures in their sus- 

 ceptibility to environment during the season of migration was very 

 plainly illustrated to me by an incident which I will relate. On 

 April 21, 1905, I visited a section of country just across the Miss- 

 issippi from New Orleans, a locality, in fact, which I have explored 



