Sept., 1913 
CALIFORNIA FORMS OF PIPILO MACULATUS 
169 
The “Southern Sierran district” includes all of southern California lying 
within the Transition Zone, and the towhee (P. m. megaloiiyx) ranges upward 
into this region from the San Diegan district, unchanged. This same subspecies 
(as distinguished from P. iii. falcincllus) ranges well up into the southern Sierras, 
near the head of Kern River, but the A'luseum's recent ( 1911) exploration in this 
region shows that most of the Sonoran species of this locality are the same as those 
of the coast of southern California, and it seems as though the term “San Diegan ' 
could well include the lower extremity of the southern Sierras east to the vicinity 
of Walker Pass. This seems to be the gap, rather than the Tehachapi as pre- 
viously supposed. 
The occurrence of P. m. falcincllus in the Sierra Nevadan district is exactly 
comparable to the manner of occurrence of P. in. inegalonyx in the Southern 
Sierran. 
P. in. falcifcr ranges through three faunal areas, but not entirely unchanged. 
The increasingly humid climate from the Santa Cruz district northward is accom- 
panied by certain changes in the towhees of the various regions, but the variations 
are slight, and as gradually accomplished as are the climatic changes. 
P. ni. curtains is confined in summer to the Great Basin district, a small por- 
tion of which extends into extreme northern and eastern California. It is the only 
representative of this group in California which is migratory in its habits, the 
known winter range of the subspecies including the extremely narrow riparian 
strip of the Colorado River valley, south to Fort Yuma. 
P. ni. clenicntae is confined to two islands of the so-called Santa Barbara 
Island faunal area. This, although a convenient name by which to designate this 
group of islands, is unsatisfactory in that the islands form anything but a homo- 
geneous group, as regards their animal life. The towhees themselves are a good 
example of this absence of uniformity. Thus P. in. clenicntae, a strongly marked 
race, occurs on San Clemente and Santa Catalina, while on Santa Cruz the spotted 
towhee is practically indistinguishable from the mainland bird. 
In studying the differences in the various races of Pipilo inacnlatns in its 
wide distribution over the state, it will be observed that there are two distinct lines 
of variation, these lines converging at the extreme southwestern corner of Cali- 
fornia. Starting from the southwestern form inegalonyx of the San Diegan dis- 
trict, gradual changes can be traced to widely different extremes at the northeast 
and northwest, respectively. 
In the towhees of the coast region, from British Columbia to southern Cali- 
fornia. the back and rump of the male bird are uniformly and intensely black. The 
difference in color between the various coast forms lies in the extent of the white 
markings of wings, interscapulars and tail, and in the intensity of the chestnut 
coloration of sides and crissum, with oregonns at one extreme, inegalonyx at the 
other, and falcifcr occupying middle ground. 
The Ifirds of the interior {falcincllus and enrtatus) have the rump almost 
invariably grayish or olivaceous ; in the exceptional instances wdiere the upper 
parts are almost or quite uniform, the black coloration is never as lustrous and 
intense as in the coast forms. 
Along both these diverging lines a gradual and unbroken series of inter- 
gradients can be follow^ed, from oregonns to inegalonyx on the one hand, and 
from curtains to inegalonyx on the other. In one feature, however, inegalonyx 
differs widely from both of the other types ; for though in coloration it may be 
considered as intermediate between them, the exceptional development of the 
tarsus and foot, especially the hind claw, sets it off distinctly by itself. 
