The type
locality of Cyanocorax unlcolor was given in the original description (Bull. Acad.
Roy. Sci. Belglque, 14, pt. 2, 1847, sance of Aug. 7: 103) simply as Mexico. It
was later (Esquisses Ornithologiques, livr. 4, 1848: pl. 17 and text) restricted to
Tabasco, although two localities in Oaxaca and also Vera Paz, Guatemala, were
induded in the range. Hellmayr (Field Mus. N.H., Zool. Ser., 13, pt. 7, 1934: 58,
footnote) has very properly challenged the supposition that this species could
occur anywhere in Tabasco and suggested a re-examination of Du Bus' type in
the Brussels Museum. I examined this type in July, 1939. It is definitely and in
detail the specimen from which was drawn the description and subsequent plate. Du
Bus had two other birds from Mexico, respectively from San Pedro, near Oaxaca, and
Tepitongo, Oaxaca but both of them are young of the year and have parti-colored
bills. These were mentioned by Du Bus but have no standing as co-types, although
someone (probably Dubois) has marked one of them as such both on the label
and in the catalogue. The type, collected by Auguste Ghiesbreght in "Tabasco,"
probably in the spring of 1838 or 1839, is a very good example, in color, and in
size an extra large one (sex not indicated; wing, 172; tail, 165), of the race cur-
rently known as Aphelocona unicolor coelestis Ridgway. That name of course
becomes a synonym of Aphelocona unicolor unicolor (Du Bus) and the south-
central Mexican race will probably be known as Aphelocoma unicolor concolor
(Cassin) Proc. Acad. Nat. Sci. Phila., 4, 1848: 26). A critical re-examination of
Cassin's type must be made, however, especially in view of the initial uncertainty
of the type locality.
September. 1942 GENERAL NOTES 213
Vol. 54, No. 3
As to the purported type locality of Cyanocorax unicolor, both Pierce Brod-
korb and E. A. Goldman inform me that there are no mountains in Tabasco any-
where nearly high enough to accommodate this cloud-forest species which south
of the Isthmus of Tehuantepec has never been taken below 7,000 feet. The
only explanation is either that Tabasco took in more territory then than now, or
that Ghiesbreght (who definitely did some collecting in Tabasco) entered an
adjacent part of Chiapas without being aware of the fact. Ghiesbreght secured other
high mountain species in "Tabasco," such as Turdus rufftorques and Peucedramus
olivaceus. One of these might have been secured in Tabasco through some for~
tuitous circumstance, but that all three could have come from there verges on the
impossible.
Sylvia taeniata Du Bus (Bull. Acad. Roy. Sci. Belgique, ibid.: 104) has always
been placed in the synonyiny of Sylvia olivacea Giraud. The type, an adult male in
the Brussels Museum, is from "Tabasco" and, although the catalogue does not so
state, was without doubt collected by Ghiesbreght in the same locality as the type
of Cyanocorax unicolor. It is the race now known as Peucedramus olivaceus auran-
tiacus Ridgway and that name now becomes a synonym of Peucedramus olivaceus
taeniata (Du Bus). The wing and tail measurements of the type are 70 and 49.5
mm., respectively. Incidentally, Bonaparte's statement (Consp. Gen. Avium, 1,
1850: 309) that the subsequent plate (Esq. Orn. livr. 6, 1850: pl. 28) was from
a specimen from San Pedro, near Oaxaca, is not correct. The type is the basis of
the plate and I may add that Wilhelm Meise made a similar notation on the tag
in 1938.
While it is certain that Chiapas, not Tabasco, is the type region of both of
the above birds, I have no first hand knowledge of the topographical details of
that state. Obviously a spot as close as possible to the Tabasco boundary should
be selected, but a definite selection may well be left to Pierce Brodkorb, in view of
his extensive work in Chiapas.--A. J. v.r Rossr, University of California, Los
Angeles.