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Show 317 same, in fact, as occurs in L. australis, in which and in L. atrata Mr. Bidgway admits it to be well marked. L. griseinucha is the only other American form of Leueostiete alleged by Mr. Bidgway to show no sexual difference in size or color. In respect to individual variation, Mr. Kidgway remarks as follows: " There is no noticeable range of individual variation among typical examples of any form, and it is only the transitional specimens connecting two reuses of one species that vary at all from the normal standard ",* etc. ( I c, p. 60). a . Regarding the subject of individual variation, we shall say little, since the immense series at our command shows that this is really insignificant77 { I. c. f p. 58). These remarks are made in reference to statements of mine quoted by Mr. Bidgway, in which I say-that " it seems probable that some of the differences whereon certain species t of Leueostiete have been founded may be only individual variations7'. This remark had reference to a series of mounted specimens in the Museum of the Boston Society of Natural History, collected at Central City, Colo., by Mr. P. E. Everett. My remarks respecting these Mr. Bidgway also quotes ( I. c, p. 55), and, without having seen them, in commenting on them in foot- notes, assigns them, with great positiveness, to his different species and varieties of Leueostiete. In point of fact, there is a considerable range of color- variation in birds of the same sex from the same localities, referable, unquestionably, to the same varieties. These affect not only the intensity of the general tints, but the areas of dusky and ashy markingsabout the head, as Mr. Kidgway's own comments under L. littoralis sufficiently show. Whether or not such specimens form the intergrading links between varieties is immaterial to the point at issue. In respect to individual variation in size, it is sufficient to say that the length of the wing varies in males of variety littoralis from 3.90 to 4.50, and in the females from 3.88 to 4.25; in variety tephrocotis ( see Mr. Bidg-way's tables), from 4.00 to 4.40 in the males, and from 3.90 to 4.30 in the females; in variety griseinucha, from 4.25 to 4.75 in the males, and from 3.90 to 4.80 in the females! It seems a priori improbable that such a wide range of individual Variation in size should obtain without there being also considerable variability in color. Such a state of things would certainly be an exceptional and noteworthy fact in our present knowledge of individual variation among birds. As the present forms a convenient opportunity for noticing some other strictures by Mr. Bidgway on some general remarks of mine respecting this group, I will add a few words respecting geographical variation among the different forms of Leueostiete. Mr. Bidgway, in commenting on my attempt " to show a correlation between the distinguishing characters o* f the different forms of this genus and the recognized general laws of geographical variation77, in which I claim the northern forms to be larger, with more ash on the head, etc., says that, respecting these statements, " there is need of correction. There is no such variation from the north sotithicard a* that stated in the passage quoted, for the northern forms are quite as brightly colored as the most southern ones, J while in the gray- headed races of L. tephrocotis it is the more southern one ( var. littoralis) which has the most gray. Thus, in this latter race the throat is more or less gray, frequently entirely gray; while, in var. griseinucha, the whole throat is black. Var. griseinucha is also much * Not italicized in the original. t Referring, among others, to L. campestris, a form Mr. Ridgway himself does not regard as even rarietally distinguishable. t Not italicized in the original. |