1887.] PROCEEDIKGri OF UNITED WTATES NATIONAL MUSEUM. 379 



For the rest, the outline of the " sternal body" of the boue in ques- 

 tion is oblong, though but slightly longer than it is wide. There are 

 six hsemapophysial facets for the sternal ribs on either costal border, 

 but there are no pneumatic foramina in the concavities between any of 

 them, nor does air gain access to the sternum of this bird at any other 

 part of it. The manubrial process is but slightly developed, while quite 

 a prominent projection curves upwards from the intersection of the 

 anterior and inferior borders of the carina. The lower mid-point of the 

 furcula rests upon the superior surface of this projection. I find the 

 keel of this bone perforated near its anterior part, and the line of junc- 

 tion with the sternal body; this latter feature is a common character- 

 istic of the sterna of certain other arctic waterfowl, as the Jaegers, for 

 instance. 



1. Antero-obliqueview of tbe sternum of Daption capensis, with the shoulder girdle in situ. Dra^Ti 

 l)y the author from a specimen collected by Dr. Streets, of the U. S. Navy, in tbe South Pacific. Life 

 «ize. 



Turning to the shoulder girdle, we find the blade of a scapula to be 

 marrow and of nearly an equal width throughout, while at the same time 

 it is gently curved for its entire length in the vertical plane. Thp head 

 of this bone is proportionately ijuite massive, and articulates with a 

 long, transverse, linear facet on the back of the corresponding coracoid. 

 A coracoid is shaped very much as we find it in Fulmarus and some of 

 the Albatrosses, where it is chiefly noted for the extraordinary width of 

 its expanded sternal extremity. (Fig. 1,) 



The head of the bone is tuberous, being directed forwards, aud in- 

 wards towards the median plane. A small foramen perforates the shaft 

 of the bone in an anteroposterior direction near its middle. Both cora- 

 coids show this perforation, and it is held in common with related types. 



The furcula in [jahixiwd, with its clavicular limbs rather delicately 

 proportioned. Its coracoidal ends are produced in tapering points, 



