Extinct Birds from Pataffonia. 7 



and the outline of the upper mandible there is some likeness 

 to Phororhacos. 



The vertebrae have articular faces of the usual avian form. 

 They are penetrated by pneumatic foramina, and the dorsals 

 and some of the cervicals bear median hsemapophyses. The 

 most remarkable point is that some of the dorsals and all 

 the caudals have their centra perforated by a remnant of the 

 notochord. The posterior caudals, which are said to be 

 procoelous, do not unite to form a pygostyle; this character, 

 as in the Ratitae, is probably '* pseudoprimitive/' In 

 Hesperornis also the posterior caudals do not unite, but in 

 this case their elongated transverse processes convert the 

 tail into a paddle-like organ quite unlike that of Phoro- 

 rhacos. 



Fiff. 3 a. 



Pelvis of riiororhacos injlatus. | nat. size. 

 (From Ameghiiio.) 



The pelvis of Phororhacos (figs. 3, 3 a) is remarkably 

 long and narrow, and at first sight has some resemblance to 

 those of Hesperornis and Colymbus, but on comparison is 

 found to differ in nearly every point. For example, in 

 neither of these birds do the pre-acetabular portions of the ilia 

 unite in a crest above the neural spines. In Hesperornis the 



