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 6o THE CONDOR VOL. VI high in air, xvhere of course some breeze is stirring. They frequently rise so high that one can scarcely detect them against the shimmering blue of the tropical sky. Suddenly one of these lofty birds takes a notion to descend, and promptly does so, by a series of long leaps, or swoops, that make one fairly dizzy. The presence of a ship excites the curiosity of younger birds, and it is a pleasant sight when a whole flock hovers around the mastheads. Here they move leisurely back and forth, but give most of their attention to the lazily fluttering pennant, which they attempt to swallow. Hardly once in an hour do these birds flap their wings, but only spread and close their deeply forked tails, which evi- dently aid them in balancing. They are complete masters of their element. Frigate birds glean a portion of their livehhood from the host of creatures which live at the surface of the ocean: flying-fishes, ctenophores, jelly-fishes, vel- lela, janthina, and in fact anything that may attract their fancy. I even observed one bird aimlessly carrying a splinter of wood, uncertain of its utility, yet unwill- ing to release it. As they never alight on the water, they seize such bits of food by swooping down in a broad curve. They are able to measure distance so accu- rately that no disturbance is created when the object is grasped. On Laysan this good judgment was utilized when the birds drank from a small pond. They flew back and forth about twenty feet above the surface, then suddenly darted downward in a long curve, and just at the right instant, like a flash, bent the head down, dropped the lower mandible, and scooped up a little water. So swift was the perforlnance that I was always a moment too late, when photographing it. The males with inflated pouches cut a most ridiculous figure, for the sac would plow a little wake, and also tend to overbalance the birds, but I saw no accidents. We were somewhat surprised and disappointed that we were not a witness to those acts of highway robbery for which the man-o'-war bird lnay be said to be justly famous. Whether they occurred during our stay of a week (May x7-2 3, x9o2) I am unable to say, but if so, must have been rather rare, because either Mr. Snyder or lnyself were usually in the field at all times of day. The explanation probably is that the warfare starts when the young frigates hatch or begin to require considerable food. As noted above not all the birds had yet deposited eggs, while the young were exceedingly few in number. The best account by far that I have ever seen of this high-handed proceeding is given by Mr. William Alanson Bryan, in his monograph of Marcus Island," and in concluding I can do no better than quote his words (1. c. p. x x4). "I have before referred to the large colonies of common brown boobies about the north point of the island. It was in the vicinity of this colony that the man- o'-war birds were most abundant. Here they vould lie in ambush for the old boobies and tropic birds as they returned from the sea heavily laden with fresh food for their young. Sitting quietly on the tree tops, or more often wheeling high overhead industriously patroling the island, out where the surf broke on the reef, these birds would keep a sharp lookout to sea for a sight of the returning fishing fleet of boobies. Sighting one (sometimes consisting of one, sometimes of several individuals) as many as half a dozen hawks would make for them under full sail, and without a moment's warning would engage a helpless bird in battle. Swooping down upon it from every side, buffeting it with their wings, snapping at a A Monograph of Marcus Island, by William Alanson Bryan, ill: Occasional Papers of the Bernice Pauahi Bishop Museum, II, No. 1 Director's Report for 19o. Honolulu 19o 3.