PHALACEOCORACID^ : CORMORANTS. 



725 



long filamentous feathers (considered by Nitzsch filoplumaceous), on the head and neck, and 

 even, in some cases, on the upper and under parts too. These feathers are commonly white, as 



is also a large silky flank-patch acquired by several 

 species. Many Cormorants are also crested with 

 ordinary long slender feathers; the crest is often 

 double, and when so, the two crests may be either 

 one on each side of the head, or they may follow 

 each other on the middle line of the hind head 

 and nape. Our species illustrate all these various 

 featherings. The naked parts about the head 

 vary with the species and afford good characters, 



Fig. 505. — Sknll ot Phalacrocorax bicrintatus. slinwint: />to. occipital style or nuchal bone; nat. size. (From 

 nature by Dr. R. W. Sliufeldt. The style is somewhat tilted upward from its natural position.) 



