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Mar., 1910 63 THE STATUS OF THE CALIFORNIA BI-COLORED By JOSEPH MAILLIARD WITI-I TWO PHOTOS BY TI-IE AIJTI-IOR BLACKBIRD Wo? species of a genus must possess at least some one characteristic which is an absolutely distinct type, form, size, or color in each--no matter how slight it may be, provided that of the one species does not overlap or inter- grade with in any degree, that of the other. This characteristic may be the meas- urement of some certain part or parts, the color of some particular feather or of all the feathers, or t.he shape of them, no matter how slight the difference provided it is unmistakable and permanent. If there is any proof of intergradation the specific difference falls to the ground, and the more or less varying forms are, for want of a better system, at present described as subspecies. The status of the genus Agelaius does not seem to be a very settled one, and it looks so far as if an insufficient number of specimens--or perhaps it would be better to say specimens from too few localities--had been compared to define the forms with certainty. The following.analysis of the descriptions of the various forms of Agelaius was originally made out by the author of this article for his own assistance in study- ing the group and with the view of making clear the subject as represented. But it is so difficult to approach this matter unaided by something of the sort that it seemed advisable to embody this analysis in the text of this paper. Absolutely nothing in it, however, is meant as a criticism of the work done by others, and all quotations are made for the sole purpose of getting at the facts. This genus has of late proved extremely interesting to me, but it has been impossible to make the descriptions in the different authorities at my command fit all the cases under observation. First came the difficulty of saying which speci- mens taken in southern California belonged to the form AgeJains p. neulralis (sup- posedly the southern California form), and which did not. Then a greater difficul- ty arose in defining where the ranges of A. g?ubernalor californicus and A. phoeni- ceus neulralis adjoined in central California. As practically all the other authori- ties to which I have had access coincide with Mr. Ridgway, who apparently has gone into the matter further than the others, I have selected his "Birds of North and Middle America", Bulletin of the U.S. National Museum, No. 50, as the best to follow in the endeavor to solve these problems. But let us see how much this work will help us out. In the key to the species of Agelaius, p. 322, Part II, leaving out those paragraphs which apply only to A. lricolor paragraph dd applies to all that follow, so we will commence at paragraph e which concerns only the gubernalorgroup. This says "middle wing coverts mostly black: or else wing 130 or more'.', the number referring of course to milli- meters. As the paragraphs f, g, and gg apply to the other forms of gubernalor only we will not consider them at the present moment. Now, in the first place, what does the expression "middle wing coverts mostly black" mean ? Are most of these coverts individually and entirely black ? Or are all these individual feathers mostly black ? From the text in the actual descriptions it seems proper to adopt the latter interpretation, tho some of the specimens under observation have one .or more of the innermost coverts wholly or partly black with no black whatever on any of the others. Then comes "or else wing 130 or more". In this case the word else can mean either that less than half (numerically) of the feathers of the middle wing coverts are ?ntirely black, that but few or none are