198 BULLETIN 121, UNITED STATES NATIONAL. MUSEUM. 



the sandy floor of the crater, which is three or four hundred feet deep, and 

 very hot, as it is protected on all sides from the wind. Only one pair was 

 seen nesting outside the crater. At Tagus Cove they nested on the hroad ledges 

 and tops of the low tufaceous cliffs. 



The following notes on the time and place of breeding of the blue-footed 

 booby, taken in conjunction with the observations of other expeditions, 

 point to an almost continuous breeding season. We found eggs, young in 

 the down, and fully fledged young at Hood Island, in September and October ; 

 both naked young and young assuming juvenal plumage at Hood in Feb- 

 ruary ; eggs, birds in down, and well-feathered young at Champion in October ; 

 young in the down at Champion in February; naked young at Brattle in 

 October; eggs and downy young at Daphne in November; large young of 

 various ages at Daphne in July; fresh eggs at Tagus Cove in March; and 

 one large young one at Tower in September. There are two young hatched; 

 but by the time they reach the partially-feathered state, seldom more than 

 one has survived. 



Mr. H. H. Bailey (1906) found the species breeding abundantly 

 on Isabella Island, off the west coast of Mexico, of which he writes : 



All around our camp, which was pitched under the low bushes bordering 

 the little bay, were pairs of boobies, one or the other of the pair covering 

 the eggs while the mate stood close by. This, however, was during the middle 

 of the day, the flshing being mostly done before ten a. m., and after four in 

 the afternoon, during which time one or the other of the birds always re- 

 mained on the eggs to keep the gulls from stealing them. The poor boobies 

 had a hard time of it here, as the man-o'-war birds nested just back of 

 them in the bushes, and lucky was the booby who passed in the entrance of the 

 bay without having to disgorge part, or may be the whole, of its day's 

 catch to this robber. Numbers of nests were on the sandy beach just above 

 high tide while others were still farther back under the shrubbery and below 

 the man-o'-war birds, and still another colony was situated on the top of the 

 rocky southwestern side of the island. All the birds were very tame, and 

 I think had not been molested since the expedition of the Biological Survey 

 in 1897, as Mr. Beermaker on landing in search of guano deposits in March, 

 1904, had not found them breeding at that time, nor had he disturbed them 

 in any way. When I first started in to get a series of eggs, I used my foot 

 to remove the booby from them, but after the first few attempts I found 

 that the sharp beak whenever it came in contact with my leg drew blood, and 

 almost penetrated through my cowhide boots, so I soon abandoned this 

 method. Two eggs were generally the complete set and but three sets of 

 three were discovered while on the island, and in some cases highly in- 

 cubated single eggs were found. In case of the latter I am inclined to think 

 the gulls had stolen one of the eggs after incubation had commenced. No 

 nest was made, a slight hollow being scratched in the sand or earth, while 

 those on the rocky side of the island simply deposited them on the bare 

 rock or on the little drifted earth that happened to be on its surface. During 

 the moonlight nights these boobies could be seen going and coming, and I 

 have no doubt their best catches were made at this time, as they were then 

 unmolested by the man-o'-war birds. Single fresh eggs gathered by the 

 crew were made into omelets, but the flavor was rather rank. 



Dr. E. W. Nelson (1899) relates an amusing experience with these 

 birds in the same colony, as follows : 



