540 
PROCEEDINGS OP THE ACADEMY OF 
white front, etc. At first sight it was referred to T. regius, but on closer exami- 
nation several important discrepancies were observed. The bill, though just 
about as long as in regius, was very decidedly smaller, weaker, with the angle 
at symphysis less developed ; it was of a clear straw-yellow, and in size and 
shape about intermediate between regius and elegans. The lateral tail feathers 
appear broader and rounded at their tip, instead of tapering and attenuated. 
An important difference is seen in the feet, the middle toe and claw being de- 
cidedly longer than the tarsus, instead of equal to it. Mr. Sclater did not label 
this bird, and I am equally uncertain what name to apply. It seems to be not 
at all improbable that it may be the S. cayana , of Latham, and, if so, would 
substantiate Gambel’s position, for it is certainly not the bird he named regia. 
Thalasseus elegans Gamb. 
Sterna elegans , Gambel, Pr. A. N. S. Ph. iv. 1848, 129. Lawrence, Gen. Rep. 
Birds, 1858, 860. Atlas, pi. xciv. 
Thalasseus elegans , Gambel, J. A. N. S. Ph. 2d ser. i. 1849, 228. 
Diag. — Th . Thalasseo regio similis ; sed multo minor, rostro graciliore, digito 
medio cum ungue tarso breviore ; corpore subtus rosaceo-albo. 
Habitat. — Coast of California. 
The most striking morphological character of this species, as compared with 
its nearest ally, T. regia , is the comparative length of the tarsus and toes. In 
regia the middle toe is, with the claw, just as long as the tarsus; while the 
same parts in elegans are verj r considerably shorter. 
This beautiful species has been so accurately described by its discoverer, and 
its affinities so correctly indicated, that any further remarks upon these points 
would be de trop. It is as yet almost unknown in cabinets. A very fine speci- 
men, in winter plumage, has been deposited in the Smithsonian by J. Hepburn, 
Esq., and is the original of the plate abo~e cited. It agrees minutely with 
Gambel’s description. 
^ ,Thalasseus acuflavidus (Cabot). 
Sterna Boysii , Nuttall, Man. Orn. ii. 1834, 276. Sed non Lath., 1790. 
Sterna can/iaca, Audubon, Orn. Biog. iii. 1835, 531. Id. B. A. vii. 1844, 87. 
Sed non Gmel., 1788. 
Sterna acuftavida , Cabot, Proc. Bost. Soc. N. H., 1837, ii. 257. Lawr. Gen. Rep. 
1858, 860. 
Thalasseus acuflavidus , ? 
Diag. — T. Thalasseo cantiaco statura, forma, Gi i rirrribnaque, omnino similis ; sed 
margine alba pogonii interni remigis primoe angustiore, nec in apicem penme 
porrecta. 
Habitat. — Atlantic Coast of North America, ranging into the Antilles in winter. 
The young of the year is considerably smaller than the adult (wing ^ inch 
shorter) as is usual in this subfamily. The bill is shorter and weaker, and is 
without any very distinct definition of angles and ridges. It is brownish black, 
the extreme point only yellowish. The crown, front and nape are brownish 
black, variegated with white, the white touches very small on the front. The 
upper parts are as in the adults ; but everywhere marked with irregularly-shaped, 
but well-defined spots and transverse bars of decided brownish black. There is 
no well formed occipital crest, until after the first moult. The primaries are like 
those of the adults. The tail, however, is very different. The feathers for 
three-fourths their length are of the color of the back ; this color gradually 
deepens, until towards the tips it becomes brownish black, — each feather having 
a terminal irregular edge left whitish. The tail, in shape, is simply deeply 
emarginate, the outer feathers being but slightly longer than the second. 
In winter the yellow tip of the bill of the adults decreases in extent and in- 
tensity of color ; the front is white, either pure or speckled with black ; the 
crown variegated with black and white ; but the long occipital crest, which does 
[Dec. 
