24 W. P. PYCRAFT, 
Aptenodytes the width is nearly as great as the length. A feature which is somewhat 
remarkable about the metapodials of the fossil forms is the fact that they are more 
completely fused one with another than in living species. In the latter, as is well 
known, the metatarsals are more or less divided by deep grooves along the anterior 
aspect of the metatarsus, while these grooves are pierced in Aptenodytes by a pair of 
intermetatarsal fenestre, and in other genera by a single foramen between the inner 
and median metatarsals. In the fossil forms only the inner groove is present, and this 
is pierced near its upper end by a small foramen, except in Kospheen/scus, in which the 
foramen is enlarged to form a long slit. 
Again, in the fossil genera the trochleze are set much wider apart than in living 
genera, and this is especially true of the trochlea of Me. II., which diverges widely 
from the trochlea of Me. III. 
This shortening of the metatarsals is in part due to the lessened use of the legs, 
but the presence of the intermetatarsal grooves would appear to be a secondary, and not 
a primitive, character, as has hitherto been supposed. Nevertheless, as we have shown 
(p. 20), in the embryo the shafts of the metatarsals are more complete than in any 
other living birds. 
Dr. Wyman, the author of the monograph on these fossils, attributes the shortening 
of the metatarsals in living penguins to their plantigrade habits, but in this, of course, 
he is in error, as these birds are not plantigrade. 
All that can be gleaned from fossils, then, is that penguins have probably 
descended from birds which possessed full powers of flight, and this probability 
becomes converted into a certainty when the embryological evidence comes to be 
examined. But the question of the precise affinities of this group must still be 
regarded as an unsolved problem, the intense specialisation which these birds have 
undergone obliterating much of the necessary evidence. 
It would seem, however, that we must regard the Steganopodes as representing 
a common ancestral stock from which have descended the Sphenisci, Colymbi, and 
Tubinares, on the one hand, and the Ciconie, Accipitres, and Anseres on the other. 
And this conclusion is based on a consideration of a number of anatomical characters 
into which there is no need to enter here. But among them I would specially mention 
two, inasmuch as they have not hitherto been used in this connection. These are the 
nature of the relations between the squamosal and parietal before their fusion, and the 
nature of the palate at the same period. 
As I propose to deal elsewhere in detail with these characters, I will confine my 
remarks thereon at present to those types immediately concerned with the subject in 
hand—that is to say, to the relationship of the penguins to the divers and petrels and 
to the Steganopodes. 
At the stage in question all are schizognathous, and the penguins and divers, like 
the Steganopodes, have a large squamosal, articulating with the hinder portion of the 
postero-infero angle of the parietal, agreeing in this with the struthious types. The 
