Nov., 1922 DISTRIBUTION OF MOLOTHRUS ATER IN CALIFORNIA 209 
from Los Angeles and Ventura counties are clearly intermediate in size and 
eolor. 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 phoeniceus 
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. 
aciculaius, 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 
Coll, No: Locality Date Wing Tail Tarsus sie at 
ase 
H 707* Buena Vista Lake May 20, 1920 Foto ae 642008 Zoe0ee laa oe 
H 708 Buena Vista Lake May 20, 1920 94 Qe G34. Pod. albs0) 9.2 
H 709 Buena Vista Lake May 20, 1920 OG:08 65:45 e243 7 aay 9.2 
H 719 Buena Vista Lake May 21, 1920 Oe Ob ool) Pee ay Sy) 
H 720 #£‘Buena Vista Lake May 21, 1920 94.0 64.4 238.2 14.5 9.4 
H 721 #£=Buena Vista Lake May 21, 1920 SAN G2:2) ea2.8. ont 9.2 
H 722 £Buena Vista Lake May 21, 1920 93.8 644 22.8 14.6 9.6 
J 798 Buena Vista Lake June 13, 1921 94.0. 63.4 23.38 14.7 a 
J 905 Buena Vista Lake July 8, 1921 9454) 595 23.2) 0 St OG 
J 906 Buena Vista Lake July 28, L921 98.3 61.4 245 144 10.5 
20101? Weldon July, IIL 100.0" “68:39 245 NiO) Shoes 
20102 Weldon Siaiky, 16 Stat! 9610 > (OG a ezon0'  1GEA SET 
21547" Bakersfield April 21, 1912 9325 65.0mm aces.  14ES 33 
29186" Mendota June 12, 1918 9372 - G3.5) zoe des) 1020 
Minimum: WR eS) yg IIE 9.2 
Maximum: NOOO) OS.8 9 24.5) 0S NOES 
Average: 95.0 64.1 23.4 15.2 at! 
*Type P 
1Collection of Donald R. Dickey, unless otherwise specified. 
2Univ. Calif. Mus. Vert. Zool. 
Molothrus 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 Set 8.9 
Maximum: 97.5 68.3 24.0 14.8 9.8 
Average: 92.8 64.6 22.5 14,2 9.3 
Molothrus ater artemisiae 
One breeding adult female from Humboldt County, Nevada, and six from Harney 
County, Oregon. 
Minimum: 96.0 64.3 250 15.6 10.3 
Maximum: 104.5 70.4 26.8 16.6 10.8 
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 heing excluded): 
100.4 67.8 25.0 15.8 10.5 
