BIRDS OF LAYSAN AND THE LEEWARD ISLANDS. 
781 
deep, chestnut, over shell markings of lilac gray edged with vinaceous. The maculations are some- 
times evenly distributed, fine spots of deep brown over broader splashes of gray, but in the commoner 
type of marking the spots are larger and more numerous at the. blunt end. The contours vary from 
blunt ovate to elongate ovate. An average specimen measures 46 by 33; an elongate one 48 by 29 mm. 
One parent always stands guard over the nestling, and the bird shown in fig. 7, pi. 3, was 
very solicitous for her young. I found one small company nesting right on the bare sand at the edge 
of the beach. Often the nest is placed under a bush, which, so far as I am aware, is never the case 
with the sooty tern. 
These terns, when excited, spread their wings slightly, tilt the tail, and walk around in circles, 
often rising a little on their toes. In flying they do not carry the bill pointed downward like our 
common tern, for example, but straight ahead like a gull. 
Sterna lunata has been recorded from Lisiansky and the French Frigate Shoals. Off the latter 
islands we found it common, and likewise observed many on Necker. Here the gray-backed terns 
nested in shallow cavities and hollows of the rocks on the more exposed portions of the island, and 
only very sparingly on the broad shelves with Sterna fuliginosa. At Bird Island we found the species 
common in June, and again in August, when there were numbers of birds in j u venal a plumage. 
Saunders gives the distribution of this tern as follows: “Paumotu Islands (Low Archipelago), 
Society Islands, Fiji group, Phoenix Islands, Hawaiian group, Laysan and Krusenstern islands, 
Caroline and Pelew islands, Moluccas, Solomon Islands, and orobably the intermediate islands of the 
Pacific.” (L. c., p. 101.) 
Procelsterna saxatilis. Necker Island Tern. 
Proeelsterna saxatilis, W. K. Fisher, Proc.-U. S. Nat. Mus., xxvi, 1903, p. 559. 
This handsome little tern we first saw off the French Frigate Shoals, particularly near the large 
rock mentioned in the narrative, and its identity was much of a mystery. When we landed on Necker 
Island the same species was soon in evidence, and its egg was found even before we realized to what 
tern it belonged. The birds are seen usually sitting quietly on the rocks, and their small size imme- 
diately singles them from the hosts of other sea fowl all around. They fly with a quick, dove-like 
wing beat, and were more suspicious of our movements than any of the other species. We never 
heard them utter a cry. Although they may perch near the “nest,” they are extremely non-committal 
as to its exact position, leaving the neighborhood whenever the egg is disturbed. In fact, only one 
bird was actually flushed off the egg, and that by Mr. Snyder as he was climbing the steep north face 
of the island. The single egg is laid in a shallow bowl-like cavity or recess in the rock with no nest, 
but occasionally a few stray quills and rubbish scattered about. (Frontispiece.) 
Although the birds were fairly common, my impression is that the nests were not nearly so 
numerous in proportion, but I have no doubt that the majority of the birds nested in inaccessible 
places along the steep face of the rock. 
All the eggs were very much incubated and we were able to save but two specimens. These are 
bluntly ovate and broadly elliptical ovate. The ground color is dull creamy white, in one specimen 
not very thickly marked with roundish, rod-shaped, Y- and U- shaped and irregular small spots of clay 
color, light sepia and wood brown, the shell marks showing various tints of bluish gray. In this 
example the spots are rather evenly distributed over the whole egg. The other egg has more numerous, 
smaller, and more regular spots, about the size of a dust shot, which are scattered over the whole 
egg, but are thicker at the blunt end. The gray spots are larger and more numerous than the brown 
ones. The two specimens measure 36.5 by 26, and 39 by 27 millimeters. 
At Bird Island this tern is abundant. We were not able to land on the rock, but from the 
Albatross saw many of them as they flew back and forth. The stomachs of those collected at Necker 
contained small silvery fishes. 
The present species is nearest Procelsterna cinerea (Gould), but instead of being ashy gray is more 
bluish in general tone, with darker upper parts, darker breast, sides, flanks, and lower tail coverts 
(instead of white of cinerea), shorter and slenderer bill, and shorter wings. In some respects it is 
intermediate between Procelsterna cerulea (Bennett) and P. cinerea (Gould). This is true of the size 
a Following Dr. J. Dwight, jr. , I have used Juvenal here and elsewhere to signify the second plumage of a young 
bird, or that succeeding the natal down. As explained by Dr. Dwight, juvenile is inexact. (See The Auk, XIX, p. 251.) 
