OSTEOLOGY OF THE PENGUINS. 



403 



presents a somewhat peculiar form in the Penguins. In form 

 it resembles a wedge, the anterior or sharp margin of which is 

 directed forwards, the base backwards towards the femur. The 

 base of the wedge is broad, deeply concave, and adapted to the 

 pulley- like surface of the lower end of the femur. The outer 



B 



Fig. 1.— Leg-bones and patella, right limb of Aptenodytes pennantii ; life-size 

 from nature. T, tibia ; F, fibula ; P, patella ; the last slightly raised 

 above its articulation with tibia. (No. 11,976 Smithsonian Collection.) By 

 the author. A, patella of Eadyptes chrysocome (from Tristan d'Acuuha), 

 outer surface, natural size. B, the same seen from in front (after Watson).' 



surface of the bone is for the most part smooth, but presents 

 about its middle a deep and narrow groove, which, commencino- 

 in front at the middle of the anterior border of the bone, passes 

 obHquely backwards, downwards, and outwards across the ex- 

 ternal surface. This groove accommodates the tendon of the 



