144 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 
new name (Ophidium beani), in honor of our excellent friend the Curator 
of Ichthyology inthe National Museum. 0. beani agrees with O. holbrookt 
Putnam, in the long and tapering air-bladder, but differs in the much 
longer head (6 in length in O. holbrooki). In O. marginatum, the air- 
bladder is ovate, truncate behind. Its form is not mentioned in the 
descriptions of O. graéllst and O. josephi. 
INDIANA UNIVERSITY, February 7, 1883. 
ON THE PROBABLE IDENTITY OF MOTACILLA OCULARIS SWIN- 
HOE AND MM. AMURENSIS SEEBOHM, WITH REMARKS ON AN 
ALLIED SUPPOSED SPECIES, M. BLAKISTONI SEEBOHM. 
By ROBERT RIDGWAY. 
The Pied Wagtails of Eastern Asia have given much trouble, as the 
numerous papers in the Ibis and Proceedings of the London Zodlogical 
Society, by Mr. Swinhoe, Mr. Seebohm, and others, testify. In a recent 
article in the first-named journal (in the number for January, 1883, pp. 
90-92) the latter author gives some “Observations on the Pied Wagtails 
of Japan,” in which is described a supposed new species (M. blakistoni) 
breeding in the Kurile Islands, South Yesso, and Askold, and conelud- 
ing with a synoptical “ Key” to the allied Asiatic species, nine in number 
The material in the National Museum is not what could be desired, 
and is by no means so extensive as that upon which Mr. Seebohm’s 
observations are based. Nevertheless, the series includes specimens 
which throw much light upon the subject, to the extent, in fact, of con- 
clusively proving that, either it is only the summer adult male of J. 
amurensis which has the back black, while the fully aduit female is undis- 
tinguishable from M. ocularis, or, else, that these two birds are identical, 
the former representing the adult male, and the iatter the adult female, 
or perhaps, in winter, both sexes. The specimens which render this fact 
perfectly obvious are a series of five skins collected by Dr. L. Stejneger, 
of the United States Signal Service, on Bering Island and at Petropau- 
lovski, Kamtschatka (one only from the latter locality). This series in- 
cludes two males and three females (the sex of one of the latter conject- 
ural, however*), the former being typical ocularis and the latter equally 
typical “‘amurensis.” There can be no doubt that they represent oppo- 
site sexes of the same species, having been obtained together, the duties 
being from May 11 to June 27. 
Granting that the gray-backed specimens hereinafter to be described 
really represent the M. ocularis of Swinhoe (and they agree in the 
*There can be no question as to the correctness of the collector’s identification of 
the sex, his invariable practice being to mark the sex only when determined by dis- 
section. 
