MUSEUM OF COMPARATIVE ZOOLOGY. 298 



change in color is equally marked. Not only do the reflections become much 

 darker at the south, but form prismatic bars across the interscapularies and 

 the feathers of the rump, especially in the South Atlantic States. In South 

 Florida and the West Indies these prismatic bars, in some specimens at 

 least, seem to lose their distinctness, evidently through the continued dark- 

 ening or increased intensity of the general color. The difference in size 

 between Florida and Massachusetts specimens is considerable, especi- 

 ally between those from South Florida and Massachusetts. Those from 

 the West Indies are still smaller ; and in comparing specimens of these 

 with others from Northern New England, the* difference is so striking 

 that it seems impossible at first to believe that both can belong to the 

 same species, yet a gradual transition between the two, through the indi- 

 viduals inhabiting the intermediate region, fully proves it. Even between- 

 Florida and New England specimens the difference is so great that, were 

 there no transition from one to the other, the two extremes might well 

 be regarded as not only valid species, but as well-marked ones. Being fa- 

 miliar with the so-called Quiscalus aglceus before visiting Florida, through 

 specimens in the Museum of Comparative Zoology from Cape Florida, I 

 had no doubt that it was a species distinct from the Q. purpureus. But 

 a subsequent study of these birds in Florida, and an examination of speci- 

 mens from various points between Florida and Northern Maine, and 

 also from the West Indies, has forced me to the conclusions indicated in 

 the above table of synonymes. 



The purple grackles of the Mississippi Valley have recently been- sep- 

 arated as specifically distinct from those of the Atlantic States, under the 

 name Q. ceneus, Q. purpureus being retained for the latter. The range of 

 Q. purpureus is given as " Atlantic and Gulf? States, north to Nova 

 Scotia, west to the Alleghanies." The New England type, however, is 

 entirely referable to the Q. ceneus, as defined by its describer. The same 

 writer also follows some of his predecessors in separating those of South 

 Florida from the Q. purpureus, under the name of Q. aglceus. But Cape 

 Florida specimens differ but little — being, in fact, scarcely distinguishable 

 except in size — from those from the St. John's River. 



Mr. Cassin, in one of his latest papers,* took fhe ground that each of 

 the larger West India Islands has a distinct species of this group, peculiar 

 to itself. That these forms, many of them evidently difficult of recognition, 

 should be distinct species is quite contrary to general principles. These 

 islands are generally separated by a distance of rarely more than a hun- 

 dred miles ; yet a near ally of these " species," the Q. purpureus (or Q. 

 ceneus as recently restricted), is admitted to range from the Gulf of Mexico 



* " A Second Study of the Icteridae," Proc. Phil. Acad. Nat Sci., 1866, pp. 403 - 417. 



