172 



MEMOIRS OF THE CARNEGIE MUSEUM 



and the transverse processes on the fourth and fifth extend out considerably beyond 

 the others of the series. 



Sternum and Shoulder Girdle. — In the article in Science cited above it was said of 

 the sternum of P. urile that it had " two shallow excavations on either side of the 

 median line, occupying the entire xiphoidal margin or border" (p. 641). This no 

 doubt was a lapsus calami, as no true Cormorant has more than one such excavation 

 upon either side of the sternal keel. Apart from its greater size, the sternum in P. 

 urile agrees in almost every particular with that bone as we described it for A. an- 

 hinga. The lateral xiphoidal processes, however, are comparatively not as long nor 

 as narrow ; nor are the costal processes of the sternum of the Cormorant relatively as 

 lofty or as slender as they are in the Darter. Otherwise the two bones essentially 



Fig. 16. Right lateral view of sternum and bones of the shoulder-girdle of a Cormorant { Plialaerocorax urile), nat. 

 size, by the author, from a specimen in the collection of the U. S. Nat. Museum. (Compare this figure with Fig. 30 

 of Plate XXVI. ) 



agree. (Compare also the sternum of Phalacrocorax albiventris, PI. XXVI., Fig. 30.) 

 Again upon comparing the several bones of the p)ectoral arch in these two forms, we are 

 once more at a loss to find any noteworthy differential characters. The os furcula 

 in each are upon identically the same pattern ; the coracoids are alike with the ex- 

 ceptions that in the Cormorant the bone is proportionately not as long ; its sternal end 



