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 78 THE CONDOR Vol. XV  juvenals (August), full-grown; new feathers, of first winter plumage, showing in some. MEASVREEb--The accompanying tble o{ measurements is self-explana- tory. It takes account of adults only, and in these care was taken to exclude examples obviously mutilated in respect to wing or tail feathers, or bill. A skin might have a perfect bill but quills too badly worn to warrant even an approxi- mate dimension, and vice versa. Such a specimen is of course taken account ot in the respect in which it does afford fairly reliable data. A percentage of error must occur, but it is the writer's belief that in taking the measurements he has erred as much on one side of the mean as on the other so that the relative size of the two subspecie s in each respect, as far as shown by the material in hand, is approximately correct. TABLE OF MEASUREMENTS (IN MILLIMETERS) Figure in parenthesis in each column opposite "average", is the number of individuals measured in each case. Bill Depth Wing Tail Culmen from of Nostril Bill tAverage 106.0 (7) 69.9 (7) 1.5 (7) 9.0 (7) 7.8 (7) l Males Maximum 107.3 72.0 12.3 9.5 8.4 L. t. tephrocotis Minimum 104.8 67.9 11.1 8.6 7.5 Average 100.9 (7) 66.2 (8) 11.4 (8) 8.8 (8) 7.8 (8) Females Maim 104.2 69.8 12.0 9.4 8.4 Minimum 97.6 64.4 0.8 8.3 7.4 t Average i04.6 (17'70.4 (16) 11.1 (18) 8.6 (18) 7.0 (18) l Males Maximum 107.6 74.1 1.7 9.3 7.2 Minimum i01.3 67.---- 10.6 8.3 6.7 L. t. dawsoni fArerage 99.8 (8) 65.8(10) 11.0 (11) 8.6 (11) 7.1 (10) Females ) Mxxium L01.7 68.1 11.6 9.1 7.3 L M i,n--d-mu m 98.1 62.1 10.6 8.3 6.9 [t is to be observed that in wing and tail length whatever difference exists is very slight, while in size of bill there is a notable difference amounting to from four to nine percent in favor of the northern race. Similar differences are shown in Ridgway's table of measurements of Leucosticte tephrocotis (Birds N. and Mid..4ruer., part , 9ox, p. 69). It would appear that as in many other birds f like distribution there is a tendency towards large size in the north. The interesting fact is here brought out that there is a pronounced greater frequency of a rounded type of wing in the Sierra Nevadan bird than with the northern bird (see accompanying table). True, the actual differences involved are slight, but they are, never-the-less, significant, the correlation being with the different amounts of migration undertaken in the two races annually. The outermost or ninth primary is longest in the majority of specimens of L. t. tephrocotis, the penult or eighth is next in length, the anti-penult or seventh is next in order; there being no variation in the succession of lengths of the rest of the primaries. In a plurality of specimens of L. t. dawsoni, the penult is long- est, the anti-penult second in length, the outermost third in length. The formula "9-8-7" 'indicates the sharpest wing, "7-8-9" the most rounded; "8'9'7" and "8-7-9" are intermediate conditions, the former nearest the sharp extreme, the latter nearest the rounded extreme.