136 



BRANCH VERTEBRATA. 



FIG. 228. 



effort.* The Petrel, sometimes called "Mother Carey's 



Chicken" is especially 

 dreaded by sailors as the 

 harbinger of a storm, but 

 scientific observation has 

 dispelled the illusion.! 



The Gulls are cosmo- 

 politan, and the true scav- 

 engers of the ocean. \ 



The Scissors-bill has its 

 long, lower mandible com- 

 pressed laterally to the 



shape and sharpness of a knife-blade, while it shuts into 



the grooved edge 



of the short upper 



one. Darting 



swiftly along, 



and cutting the 



water with its 



lower m andible, 



the smaller fishes 



Thai as sid' rb ma pe liig'i ca. 

 Stormy Petrel. (\.) 



FIG. 229. 



chops nV gra. Scissors-bill. ('.) . 



struck by it, slide 



upward to the mouth and are immediately swallowed. 



. * It is found south of the equator, but there are other species on the western 

 coast of North America. 



t Gleaning its scanty pittance from the whirling surges of the sea, and 

 making its appearance in great numbers just before a storm, seeking food and 

 shelter in the wake of the vessel, it has been charged with creating the tempest. 

 Its flesh contains much oil, and the natives of the Faroe Islands are said to make 

 a lamp by drawing a wick through the body of a very fat one, and lighting the 

 end which projects from the beak. 



J The different species vary greatly in coloration of plumage white with va- 

 rious shades of black predominating. But most remarkable are the varying hues 

 of the same individual at different seasons of the year, and at different ages, 

 making identification often very difficult. 



In the swiftest swallow, the expansion of wing is twice the length of 

 body ; in the Scissors-bill it is much greater, hence more powerful. 



