Nov., t922 DISTRIBUTION OF ftgOLOTHRUS ATi?R IN CALIFORNIA 209 from Los Angeles and Ventura counties are clearly intermediate in size and color. To the east, the Sierra Nevada Range forms an effective barrier to the interbreeding of californicus with either artemisiae or obscurus. Future collect- ing in the Sacramento Valley may disclose an intergradation with artemisiae in that region. In working over the series of the present subspecies, it has particularly in- terested the authors to find this race apparently reaching its maximum devel- opment in wing length and in attenuation of bill on the South Fork of the Kern River. It is this same mountain valley which has produced Agelaius phoeniccus aciculatus, and it is of further interest to note that the distinctions which serve to separate Agelaius p. neutralis, of the San Diegan district, from Agelaius p. aciculalus, are paralleled in many respects by those which differentiate Molo- thrus a. obscurus from Molothrus a. californicus. MEASUREMENTS Molothrus ater californicus FEMALES (all from California): Depth Coil. No. ? Locality Date Wing Tail Tarsus Cu]rnenBillat Base H 707* Buena Vista Lake May 20, 1920 93.3 64.6 23.0 15.1 9.9 H 708 Buena Vista Lake May 20, 1920 94.2 63.4 23.4 15.0 9.2 H 709 Buena Vista Lake May 20, 1920 96.0 65.4 24.3 14.7 9.2 H 719 Buena Vista Lake May 21, 1920 95.3 65.8 23.4 15.2 9.9 H 720 Buena Vista Lake May 21, 1920 94.0 64.4 23.2 14.5 9.? H 721 Buena Vista Lake May 21, 1920 94.1 62.2 22.8 16.1 9.2 H 722 Buena Vista Lake May 21, 1920 93.8 64.4 22.8 14.6 9.6 J 798 Buena Vista Lake June 13, 1921 94.0 63.4 23.3 14.7 9.3 J 905 Buena Vista Lake July 8, 1921 94.4 59.5 23.2 15.0 10.0 J 906 Buena Vista Lake July 8, 1921 98.3 61.4 24.5 14.4 10.5 201012 Weldon' July 6, 1911 100.0 68.3 24.5 17.0 '10.3 20102'-' 'Weldon July 6, 1911 96.0 66.7 23.0 16.4. 9.7 21547 -? Bakersfield April 21, 1912 93.5 65.0 22.8 14.8 9.3 29186 -? Mendora June 12, 1918 93.2 63.5 23.4 15.8 10.0 Minimum: 93.2 59.5 22.8 14.4 9.2 Maximum: 100.0 68.3 24.5 17.0 10.5 Average: 95.0 64.1 23.4 15.2 9.7
- Type
?Co]]ection of Donald R. Dickey, unless otherwise specified. '-'Univ. Calif. Mus. Vert. Zool. Moloihrus ater obscurus Eleven breeding females from Imperial Valley, and five from the San Diegan District. Wing Tail Tarsus Culmen Depth Bill at Base Minimum: 90.0 61.0 21.2 13.7 8.5 Max,'mum: 97.5 68.3 24.0 14.8 9.8 Average: 92.8 64.6 22.5 14.2 9.3 Moloihrus ater artemisiae One breeding adult female from Humboldt County, Nevada, and six from Harney County, Oregon. Minimum: 96.0 64.3 25.0 15.6 10.3 .Maximum: 104.5 70.4 26.8 16.6 ' 10.? Average: 101.0 67.2 25.9 15.9 10.5 Average of eight breeding females from_ Death Valley, Mono Lake, and Indepen- dence, selected as showing that artemisiae in nearly typical form occurs at these south- ern points (intergrades with obscurus being excluded): 100.4 67.8 25.3 15.8 10.3
