NORTH AMERICAN BIRDS. 61 



two eggs. These are white, covered with a calcareous deposit; sizes range from 

 2.45 to 2.60 long by 1.67 to 1.75 broad. 



114. 1. BLUE-FOOTED BOOBY. Sula gossi Ridgw. Geog. Dist Islands in 

 the Gulf of California, south to the Galapagos. 



Between the 15th and 28th of March, 1888, the late Col. N. S. Goss found this new 

 species breeding on the San Pedro Martir Isle, situated in the Gulf of California 

 about midway between the shores. It is a rock about one and a half miles long, 

 nearly as broad, and about 1045 feet in height, a little north of latitude 28. Colonel 

 Goss states that the birds make no nests and lay but one egg; this they drop upon 

 the smooth rock, often in exposed situations, preferring the places where the 

 guano has been removed and, in many cases, close beside the winding paths that 

 were hourly trodden. No young birds were found, and from the condition of the 

 many e^gs examined, he was of the opinion that the birds do not commence laying 

 before the first of March. The average measurement of twenty-one eggs is given 

 as 2.42x1.60. The ground color is greenish-blue, coated with a dull white chalky 

 substance, but generally more or less stained with guano that generally gives them 

 a dirty buff wuite look; m form elliptical ovate.* A specimen of the egg of this 

 species in the collection of the late Capt. B. F. Goss measures 2.34x1.60. 



115. BOOBY. Sula sula (Linn.) Geog. Dist. Tropical and sub-tropical coasts 

 and islands of America, north to Georgia. 



The Booby Gannet is said to breed on some of the islands about the extreme 

 southern coast of Florida. In the Bermuda Islands, anu in some OL the Bahamas, and 

 many of those along the coast of Central and South America, this Gannet congre- 

 gates by thousands at its breeding places, where it deposits its eggs on the sand 

 of the beaches, or on the bare rock; no nest whatever is made. The food of this 

 species consists chiefly of flying-fish and small mullets, which they disgorge in a half 

 macerated state into the open mouths of their young. Audubon found mullets weigh- 

 ing more than a half a pound in the bodies of the gannets he examined. In various 

 islands of the southern oceans the Boo*>y constructs its nest of sticks and weeds on 

 bushes and low trees. Here it is said to lay but one egg. Observations of those who 

 have collected in the West Indies disclose the fact that the complete nest complement 

 is two eggs. These are of a uniform dull, chalky white in color, with great variations 

 in sizes, measuring from 2.16 to 2.64 long by 1.50 to 1.57 broad. 



115.1. BREWSTER'S BOOBY. Suld brewsteri Goss. Geog. Dist Islands of 



the Eastern South Pacific Ocean, northward to Lower California. 



This is another new species of Booby which was found breeding by Colonel Goss 

 on San Pedro Martir Isle in the Gulf of California. The birds were not wild, but 

 their nesting places, as a whole, were not in as 'exposed situations as those of the 

 Blue-footed, they seemed to prefer the shelves and niches on the sides of the rocks. 

 They lay two eggs, and in all cases collect a few sticks, sea-weed, and often old wing 

 and tail feathers; these are generally placed in a circle to fit the body, with a view, it 

 was thought, to keep the eggs that lie upon the rock from rolling out. There is but 

 little material on or aoout the isle out of which a nest can be made. Colonel Goss 

 says the birds must commence laying as early as the 10th of February, as young were 

 found in many cases from half to two-thirds grown. The average measurement 

 of seventeen eggs is given as 2.44x1.60. In color and form, as well as size, they are 



* The Auk. V, p. 242. 



