132 THE CONDOR Vol. XXIV 
Mouse Gray of Ridgway’s Nomenclature of Colors than to anything else, thus 
according with Dr. Fisher’s description of the back of frontalis, in which he 
states positively that the back is ‘‘mouse gray’’, while he gives the back of car- 
bonacea as ‘‘warm slate gray’’. In these northwest coast jays there is the dis- 
tinct blue wash over the darker parts, when viewed in the right light, and in 
none of these does the dark mantle extend as far posteriorly as it does in car- 
bonacea and stelleri, but shades more rapidly into the blue of the lower back and 
rump, as is the case with typical frontalis. What slight brownish tinge there 
may be on some specimens of these coast birds is mostly confined to the seap- 
ular region. The blue of the lower parts of the Requa birds is decidedly darker 
than that of any of the specimens secured farther south, that is to say, farther 
south than Humboldt Bay, and below. We did not have an ovportunity to se- 
cure any jays between Requa and Humboldt Bay. These should show some grad- 
ation in regard to this darker coloration. 
The jays taken in the end of September and beginning of October at Knee- 
land, Petrolia, and Thorn, were all of a rather lighter shade than those from 
Requa, but were all of the same general tone of coloration. Placing one of these 
alongside a bird of corresponding date from the San Francisco Bay region 
brought out the difference in a most convineing manner. A friend, whose ar- 
tistic line of business calls for a keen appreciation of colors, was asked to exam- 
ine the different jays here concerned and to give an unbiased opinion as to the 
correctness of my diagnosis of their color schemes. With absolutely no knowl- 
edge of birds, this friend without hesitation picked out the northwest coast birds 
from those of the central coast and placed them with the frontalis, as being most 
closely allied to that form, and secondarily with stellert. This was done, of 
course, without looking at the labels, and was a strong confirmation of my diag- 
nosis. 
Recently I had the pleasure of going over with Dr. Fisher, the series of sev- 
enty-eight specimens of Cuanocitta secured during the Academy field work along 
the northwestern California coast in 1921, and directing his attention to the 
points I am endeavoring to bring out in this paper. He was greatly interested 
in the matter, and finally decided that he had not had sufficient material, nor a 
sufficiently extended knowledge of conditions pertaining to the subject at the 
time of writing his paper already referred to, upon the status of these jays, to 
do the subject full justice. 
CONCLUSIONS 
As a result of our work in the field. and of the examination of a large num- 
ber of specimens (from the Museum of Vertebrate Zoology, University of Cali- 
fornia, from the Mailliard collection, and from that of the California Academy 
of Sciences), I have arrived at the conclusion that the crested jav along the 
northwest coast of California commences with the nearly typical Blue-fronted 
Jay (Cyanocitta stellert frontalis) in the vicinity of Freestone, Sonoma County. 
just north of the oven non-coniferous country that extends east from Tomales 
Bay to the Napa Valley; that toward the north along the coast these birds grow 
gradually darker. the darkest California specimens being found in the county of 
Del Norte in the northwest corner of the state; that this darkness increases north- 
ward aiong the Oregon and Washington coasts until merged into typical stelleri; 
that toward the interior of California, corresponding to the decrease of humidity 
