STERNA OF TRUE DIVERS. 377 



the grebes), but not articulated to it. The branches 

 of the clavicle are flattened laterally, rather slender 

 at the middle point, but much enlarged at their union 

 with the coracoids and the scapulars. They abut 

 against the latter bones by a head consisting of two 

 processes, and the coracoid has its enlarged head 

 applied over the junction of the two, and a process 

 underneath, which bears up the head of the clavicle. 

 The scapulars are rather slender, bent into a regular 

 curve, and tapering a little toward their points. The 



annexed figure of the sternal apparatus of the red- 

 throated diver (Colymbtcs septentrionalis), in the propor- 



