556 



ALEXANDER WETMORE 



specialized, so that, though several species of Phalacrocorax, Nan- 

 nopterum, and two species of Anhinga were examined, they were 

 not directly comparable. In the following table I have drawn up 

 in parallel columns the salient differences in the distal end of the 



Fig. i. — Lower surface of distal portion of femur (type) of Palaeochenoides 



nuoceanus. 



femur in the species enumerated in the two groups. An asterisk 

 indicates which group Palaeochenoides resembles in the characters 

 designated. 



Steganopodes 



Intercondylar notch more shallow, 



broader. 



Femur pneumatic* 



Condyles little elevated on dorsal 



surface, merging in a long gradual 



slope into shaft.* 



Ventral surface of femur behind 



condyles flattened, lateral margins 



angular or very slightly rounded.* 



Tuberosity above fibular facet of 



outer condyle lateral, following 



line of shaft.* 



Anseres 



Intercondylar notch deep, narrow.* 

 Femur non-pneumatic. 

 Condyles well elevated on dorsal 

 surface, rising abruptly from shaft. 

 Ventral surface of femur behind 

 condyles more rounded, lateral 

 margins strongly rounded. 

 Tuberosity above fibular facet of 

 outer condyle extending at an 

 angle across outer third of shaft. 



It is seen that in four of these major differences Palaeochenoides 

 agrees with the Steganopodes, while in only one does it approach 

 the Anseres. Other differences of less constant value are present 

 between the two groups. In most of the anserine birds the con- 



