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Variation of Birds in a State of Nature by Frank Russell, 1892

Variation of Birds in a State of Nature by Frank Russell, 1892, Page 22

parts was arranged from the measurements of one hundred specimens selected from the whole number (500) measured. It therefore contains more than three times the number in the diagrams of the other species. Owing to limited space but one half the total length and length of wing have been taken. The wing shows a general increase in length toward the right but hardly in proportion to the great increase in length. Marked irregularity is noticeable in no's 205, 311,and 314, where the wing does vary with the length it is not to the same extent, and more frequently not all. In forty three cases the variation of wing is in the same direction as in the tail, but seldom in the same degree. The tarsus and middle toe vary together in about fifty specimens, the lines meet and intercross so that reference to the number of the specimen is necessary to distinguish them. The length of culmen is the only line which does not show less variation in the specimens of average length than elsewhere, and the hind toe which varies quite uniformly, varies little in these birds.
In general we conclude that those birds which vary most from the mean measurement show a greater variation in the relative size of parts.

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parts was arranged from the measurements of one hundred specimens selected from the whole number (500) measured. It therefore contains more than three times the number in the diagrams of the other species. Owing to limited space but one half the total length and length of wing have been taken. The wing shows a general increase in length toward the right but hardly in proportion to the great increase in length. Marked irregularity is noticeable in no's 205, 311,and 314, where the wing does vary with the length it is not to the same extent, and more frequently not all. In forty three cases the variation of wing is in the same direction as in the tail, but seldom in the same degree. The tarsus and middle toe vary together in about fifty specimens, the lines meet and intercross so that reference to the number of the specimen is necessary to distinguish them. The length of culmen is the only line which does not show less variation in the specimens of average length than elsewhere, and the hind toe which varies quite uniformly, varies little in these birds. In general we conclude that those birds which vary most from the mean measurement show a greater variation in the relative size of parts.