776 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
places it is replaced b} ? Paffinus cuneatus , which thus encircles the lagoon in a ring 
inside of the immense AEstrelata colony. 
The distribution of other forms is about as regular as these. Not only is there 
a horizontal distribution, but also a vertical. The number of breeding birds is so 
prodigious that favorable space is at a premium, and several species live one above 
the other. Thus, in burrows beneath the ground are found JEstrelata and Puffirius 
cuneatus , and above them Sterna; while in bushy areas Phaethon and Pufinus 
nativitatis may take the place of Sterna. Still higher, in shrubs, Telespiza and 
Acrocephalus make their nests, the topmost branches being occupied by Sula 
piscator , Fregata aquila , and Micranous hawaiiensis. As Dr. Schauinsland puts it, 
“the comparison with series of flats in large towns is opportune.” 
The birds do not all breed in greatest numbers at the same time, but there is a 
certain succession. This has been well stated by Dr. Schauinsland, whom I quote 
in translation: 
In spite of this excellent use of all the space at their disposal, the birds which have chosen 
Laysan for their breeding home would not be able to find satisfactory places if they all arrived at the 
same time. They are therefore obliged to take turns, so that some species of sea birds leave the place 
as soon as their young are strong enough to fly, and while the former occupant is leaving the new- 
comers already begin to arrive. Thus there is a constant coming and going, and it follows that breeding 
species are found at almost every season of the year, a fact which is remarkable even in the tropics 
where the breeding season is generally less regular than in our latitudes. In this way a most definite 
succession, which probably dates back thousands of years, takes place year after year in the arrival 
and departure of certain species. « 
During the seven day's that the Albatross remained near Laysan, Mr. Snyder 
and myself remained on shore, the guests of Mr. Max Schlemmer, to whom the 
success of our visit is largely due. We were thus able to verify our few observations 
on the habits of the birds many times, and Mr. Schlemmer gave us valuable hints as 
to the location of the land birds’ nests. He also presented us with a small collection 
of eggs. Various members of the party came ashore at different times, and a survey 
of the island was made by the officers of the ship. Much of our time was necessarily 
taken with the preparation of specimens, but as often as possible daylight hours 
were given to photography' and observation, while the less interesting but necessary 
labor of caring for skins was left till after sundown. 
On the evening of May 23 the Albatross weighed anchor, and on the afternoon 
of May 28 arrived at French Frigate Shoals. This is an extensive reef under a few 
fathoms of water, with four sand islands projecting above. The shoal is rudely 
crescent-shaped, the hollow toward the south, and on its southern edge is a lava rock 
rising 120 feet above the sea. The larger islands are covered with vegetation, but 
we were unable to land on account of rough water on the shoal. 
. Birds were plentiful, especially around the tall rock. Early in the morning 
terns fairly swarmed over the largest sand islet. We saw here for the first time a 
graceful little gray tern, Procelsterna saxatilis, which was later captured on Necker 
Island. It was undoubtedly nesting on the tall rock. Other birds which were 
positively identified were: Sterna fuliginosa , Sterna lunata , Gygis alba kittlitzi , 
Anous stolidus, Diomedea immutabilis , Dlomedea nigripes , Puffinus nativitatis , Sula 
\cyanops , Sula piscator, Sula sula , and Fregata aquila. 
Urei Monate aul einer Koralleninsel, p. 49. 
