PREFACE 15 



last named being that of the Bounty Islands shag, which was 

 added in 1901, and makes a total of abont 190 species. 



In the measurements, the length of the wing means the length 

 from the flexure at the wrist-joint to the tip of the longest 

 feather. The tarsus is what is ordinarily called the leg; it lies 

 between the drumstick and the foot. 



