124 University of California Publications in Zoology [Vou. 30

assertions are all rather vague. In this museum there are approxi-
mately 200 specimens of lewcophrys, 270 of gambelii, and 200 of
nuttalli. There is not one equivocal specimen in this series, not one
that can be said to illustrate in even the slightest degree intergradation
between any of the forms. Nor have I seen intermediates in other
collections. If any such do sporadically occur it seems to me that
they should be regarded as hybrids rather than geographic intergrades.
Riley (1912, pp. 66-67) has given conclusive evidence as to conditions
at the one place where the ranges of leucophrys and gambelw are
known to abut. Each retains its specific identity. As far as I know,
the breeding range of nuttalli is widely separated both from that of
leucophrys and of gambelu.

The different songs of these three birds also is something that can-
not fail to impress one. When in addition to the consistently uniform
external characters found in each form, there are also such differences
of song and breeding ranges as are seen, it seems to me that every
condition is met whereby they should be accorded specific rank.

LIST OF FORMS OF THE WHITE-CROWNED SPARROWS OF THE GENUS
ZONOTRICHIA
1. Zonotrichia leucophrys (J. R. Forster). Eastern White-crowned Sparrow.
2. Zonotrichia gambelii (Nuttall). Gambel White-crowned Sparrow.
3. Zonotrichia nuttalli Ridgway. Nuttall White-crowned Sparrow.

Zonotrichia coronata (Pallas). Golden-crowned Sparrow

There is a small and yearly diminishing list of North American
birds, the breeding habits of which are almost or quite unknown, and
the golden-crowned sparrow has been one of the few passerine species
included in that category. It is true that many years ago detailed
accounts were published professing to give particulars of the nesting
of this bird, but those were cases of mistaken identification and so far
as I know there has not yet been printed any unquestioned account
of the breeding of the golden-crowned sparrow. I was, indeed, under
the impression for a time that nests and eggs taken by Major Brooks
and myself in the Atlin region were the first authentic sets to be col-
lected, but, as I learned, there are sets in the collection of Colonel
John E. Thayer, Lancaster, Massachusetts, that were taken some years
ago. Through the courtesy of Colonel Thayer details regarding these
sets are given below.