Nov., 1905 | 
Atratus versus Megalonyx 
BY HARRY S. SWARTH 
T HAT the accepted arrangement of the towhees of the southwest, of the Pipilo 
maculatus group, is an arbitrary and artificial one, is a fact that is evident to 
anyone who studies the matter at all carefully. 1 refer particularly to 
P. in. megalonyx and P. m, atralus, as at present distinguished; atratus being con- 
fined to the coast district of southern California from the Sierra San Fernando, 
and Sierra San Gabriel, south into northern southern California, while megalonyx 
occupies the extensive territory lying between the Pacific Ocean and western 
Texas and from central California and Wyoming, south into northern Mexico. 
Now in the region outlined above I believe that two forms of Pipilo maculatus may 
Ire distinguished, but the dividing line should not be drawn as it is at present. 
That atratus is simply a synonym of megalonyx is, I believe, a demonstrable fact. 
That such is the case is by no means ^ 
a new idea with me, for Pacific coast , 
ornithologists have generally re- 
fused to recognize the race (see 
Grinnell, Condor IV, 1902,23; Check 
list of California Birds, 58), but it is 
only lately that I have been able to 
get together material to properly 
demonstrate the facts of the case. 
The type of Pipilo megalonyx was secured by 
Xantus at Fort Tejon, southern California, 
and as this towhee is resident wherever found 
in California, it makes little difference whether 
this particular specimen was a breeding bird 
or not. Pipilo maculatus atratus was described 
by Mr. Ridgway from specimens shot by Mr. 
Grinnell in the vicinity of Pasadena, some 
sixty miles distant from Fort I'ejon and in the 
same faunal area. The principal distinguish- 
ing characteristic is the excessively dark colo- 
ration, with glossy black rump, uniform with 
the back. Of Pasadena specimens there 
was an abundant supply to be had, but skins from the type locality of megalonyx 
appeared, until recently, to be entirely lacking in California collections. In May, 
1904, I made a short trip into the mountains southwest of Fort Tejon, and 
secured seven towhees at a spot about twelve miles from the fort, while a few 
weeks later Mr. Grinnell secured additional specimens at Mount Pinos, which I 
now have before me. 
In all I have examined in this connection about one hundred and fifty speci- 
mens, from the following localities: Los Angeles County (mostly Pasadena spec- 
imens) 75; Mt. Pinos and Fort Tejon, 13; Piute Mountains, Cal., 1; Monterey, Cal., 
5; San Francisco Bay region (P. m.falcifer), 15; Huachuca Mountains, Arizona, 20; 
scattered localities in Arizona and New Mexico, 9; besides specimens of P. m. 
arcticus. 
Taking up the series from Los Angeles and Pasadena first, it appears that the 
LINED AREA. P. M. MEGALONYX: DOTTED 
AREA. P. M. MONTANUS: CROSSES, PROBABLE 
AREA OF INTERGRADATION. 
No. i. Huachuca Mountains., type locality ol 
P. 111. montanus. 
No. 2. Pasadena, type locality of P. m. atratus. 
No. 3. Fort Tejon, type locality of P. m. 
megalonyx. 
No. 4. Palo Alto, type locality of P. in . falcifer. 
