Sea PROCEEDINGS OF THE NATIONAL MUSEUM. 339 
given as distinctive of this form, viz, (1) general large size; (2) longer 
first (rudimentary) primary; and (3) more vivid yellow color of the 
underparts. Several of the thirty-one specimens before me can be thus 
distinguished (for instance, U. S. Nat. Mus., No. 92557, Kamtchatka; 
Nos. 88624, 91374, Hondo, Japan; Jouy, No. 1445, Corea; Henson, 
Nos. z, aa, Yezo, Japan) as true Ph. xanthodryas, and U.S. Nat. Mus., 
Nos. 92551, 92554, 92556 (Bering Island), 88504, 88505 (Amoy, China) 
Henson, No. x (Hakodate, Japan), and all the Alaskan specimens* as 
Ph. borealis, but other specimens will only show one or two of these 
characters in all possible combinations. Thus U. 8S. Nat. Mus., Nos. 
89158, 106607 (Bering Island), and Petersen’s No. 28 (Kiusiu, Japan), 
are Ph, xanthodryas as far as the first primary is concerned, but Ph. 
borealis according to color, while the first mentioned has the size of the 
former and the two others are not larger than ordinary Ph. borealis. 
Henson’s No. w (Hakodate, Japan), on the other hand, belongs to the 
last mentioned form by its general size and the first primary, while it 
is colored like Ph. xanthodryas. Wenson’s No. y (Hakodate) is a Ph. 
xanthodryas by its size, a Ph. borealis by its color, with the first pri- 
mary intermediate. U.S. Nat. Mus., No. 96254 (Blakist., No. 1879; Ha- 
kodate ) is also a Ph. canthodryas by size, and partly by its color, but 
its first primary does not reach beyond the longest primary coverts. 
The result is that if you arrange your birds in two groups according to 
either one of the three diagnostic characters, the two groups will con- 
tain different specimens every time. 
It cannot be denied, however, that there is a general tendency in the 
larger birds to have a proportionally larger first primary and a yellower 
tint, and it may be that this tendency would be more striking were all 
the specimens properly sexed. It is also somewhat significant that we 
*Three additional specimens from Alaska bear out my suggestion (Res. Orn. Expl. 
Kamtsch., pp. 303-304) that the Alaskan colony consists of birds of smaller dimen- 
sions than those from Kamtchatka and Japan, and that their migration route does 
not touch these countries. I feel quite confident that the two forms are subspecifi- 
cally distinct. In evidence I offer the following 
Measurements. 
| 
o 
BSNat, |; = Sox . CuI 
ee Collector and No.) and Locality. Date. a a F 
1ge A S 3} = 
op | 2 is 
rete lanes Z 
b in} te a 
Pe ya| A | & 
= — = ~-- = ee Sy a ee = 
106650 | Townsend, 11654. ad.| Kowak R. Alaska... .. Aug. 1,1885 | 60 | 45] 9.5 8 
101217 | Johnson, 4...--,- ad: Alas kalo: 250.2) Si5<2 June19,1884} 65 | 48 |.--.-. 9 
101216 | Johnson, 12...... UC: 5. <d OSM ane eee eee SPE Ope Se 62 | 44] 10 10 
45909 | Pease, 178....---. ad.| St. Michaels, Alaska.-| Aug.16,1886] 60 | 43 |.-- -. 9 
75416 | Nelson, 438....-... Fr Hel res sete pe ee ge Aug. 24,1877 | 60 Oe ea 7 
75415 | Nelson, 462....... ads |acdOre. aet ee oar eee Aug.31,1877| 65 | 46 }....-. 9 
Average dimensions of 6 specimens... -.........-..-.|....-.---.---- | 62 | 45 |..c.-. 8.7 
a = — ee ——- eee 
