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THE CONDOR 
Vol. XVI 
Mall attract attention, than that a statement of probable affinities will be re- 
membered from one out of a mass of papers. 
Although it is of course a matter of regret that there is but one specimen 
of this island subspecies at hand, I believe that the appearance of this single 
bird justifies the naming of the race to which it belongs. Although there is 
great variation shown in series of Salpinctes obsoletus, both as regards shades 
of gray or brown, and character of spots, bars, or streaks, on various pai’ts 
of the plumage, this specimen stands absolutely outside of this range of var- 
iation, so that I do not believe that there is any question of its belonging to 
this species. From guadeloupensis it is not so readily distinguished, at least 
as regards color, but the measurements lie outside the limits reached by that 
form. As in its variation from typical guadeloupensis there is an apparent 
approach toward the characters of obsoletus, it might be considered as illus- 
trating intergradation between the two, but for the present at least, in view 
of the many peculiarities of distribution observed in the genus, it seems best 
to consider obsoletus and guadeloupensis as distinct species. 
We are probably safe in assuming that the Eock Wrens of all the islands 
off the coast of California, as well as those of most of the Lower California 
islands, are derived from the mainland form Salpinctes obsoletus. In fact, 
in most cases they are not to be distinguished, though it does seem to me that in 
the island birds throughout there is to be detected a slight general tendency 
toward lengthening of eulmen. In the Santa Barbara group this tendency 
has reached, on San Nicolas, most remote from the mainland, a stage where 
we are perhaps justified in recognizing the variation in nomenclature, and 
considering the San Nicolas Eock Wren as a separate subspecies. There is 
another slightly differentiated island form of obsoletus, 8. o. exsul (not seen hj’’ 
me), from San Benedicto Island, of the Eevillagigedo group, off the coast of 
western Mexico. Of additional island localities there are at hand specimens 
from most of the Santa Barbara islands, and from the following Lower Cali- 
fornia islands : The Coronados, San Benito, Cerros and Ildefonso. None of these 
are to be distinguished with certainty from typical 8. obsoletus. 
Thus there is on the mainland coast of California and Lower California, 
and on most of the adjacent islands, the Eock Wren, Salpinctes obsoletus, in 
its three very slightly distinguished races, obsoletus, pulverius and exsul. 
In the midst of this general range there is found on two islands, Guadalupe 
and San Martin, a sharply differentiated form, Salpinctes guadeloupensis, 
apparently divided into two races, guadeloupensis and proxinius. Bearing in 
mind the above facts as regards distribution, and also the degree and kinds 
of difference distinguishing the forms, it seems to me that in the light of our 
present limited knowledge of the subject, it is best to regard Salpinctes obso- 
letus and S. guadeloupensis, as distinct species, the first composed of several, 
the second of two, different forms or subspecies. In other words, 
it is the treatment accorded these forms in the A. 0. U. Check-List (1910, 
p. 336) that seems to me the more reasonable, rather than the view 
expressed by Eidgway (1904, pp. 643-653) in his recent study of the group. 
At the same time recognition must be accorded the possible significance of 
the peculiar juvenal plumage of Salpinctes obsoletus notius (not seen by me). 
In this Mexican form the young is described by Eidgway (1904, p. 648, foot- 
note) as being similar to the corresponding stage of guadeloupensis, and this 
may be an indication of close relationship between these two forms, though 
the geographical position of notius adds no emphasis to such a theory. The 
