154 The Wilson Bulletin — No. 97 



that the occupant of one was often disturbed by the flopping 

 wings of its neighbor. The male takes an active part in the 

 nest building and in some instances builds a nest even before 

 finding a mate. In such cases, after his work is finished he 

 sits quietly holding down his claim. If by chance he is 

 frightened from; his post, thieving neighbors of the same spe- 

 cies will carry away the nest stick by stick. 



In the same buoyancy of spirit in which the pea-cock 

 spreads its resplendent tail and the argus pheasant its gor- 

 geous wings, this bird inflates the gula-sack to a size so large 

 that it often conceals from the front the bird's entire body, 

 save only the beak and eyes. Evidently Nature intended this 

 embellishment to. take the place of a song as the creature has 

 only a hoarse cackle, far from winsome, which, nevertheless, 

 is kept up incessantly while mating. When a female comes 

 near the nest, the male becomes very much excited, bending 

 back its head, swaying its pouch from side to side, partially 

 spreading its wings and tail, and flopping about in the most 

 ridiculous manner. At times it will rub its pouch against the 

 female, who, true to the instincts of her sex, pretends not to 

 be interested, unless by chance a rival appears, whereupon 

 my lady not only takes an interest but proceeds to drive away 

 the intruder. After the single egg is laid the male does not 

 inflate the gula-sack, excepting on rare occasions. 



The birds seem not to mind the presence of man in their 

 rookeries, and will not leave their nests unless the intruder 

 gets very near. One large male refused to leave the egg he 

 was guarding until touched with a stick, whereupon, with 

 gula-sack inflated and open mouth he came directly at the of- 

 fender. His aspect was not unlike that of an angry sitting- 

 hen, although much more formidable. This demonstration 

 was so unexpected that it was impossible to make a photo- 

 graph, but most fortunately the year following this incident, 

 Mr. Alfred Bailey, who visited Laysan with a party sent out 

 by the U. S. Department of Agriculture, in making a snap- 

 shot of the man-o'-war rookery, caught one of the birds in 

 the same act without being aware of it until the plate was 



