8 A MANUAL OF THE BIRDS OF AUSTRALIA, 
a further separation of the Austral-Neozelanic forms, Hudyptula, Eudyptes and 
Megadyptes from the Afro-Magellanic Spheniscus. The two families here recognised 
are easily distinguished by the bill formation, the thick-billed forms also having a 
more northerr: distribution than the thin-billed ones, the largest of which are confined 
to the Antarctic Continent. As evidence of the value of the so-called superficial 
features we associated Pygoscelis with Aptenodytes from a study of these alone, and 
upon consideration of the known anatomical and osteological characters we find 
absolute confirmation of our association. 
Osteologically the skull has the palate schizognathous, the nostrils holorhinal 
and basipterygoid processes are absent ; the pterygoids are unique in size and shape, 
being proportionately very large and flattened, and perforated near their junction 
with the palatines ; the lachrymals have their descending process with a large foramen ; 
large supraorbital grooves are usually present. The sternum has a well-developed 
keel, the cervical vertebre are fifteen in number and the dorsals are opisthoccelous 
in character, the furcula prominent and the scapula unique in shape, being very large 
and posteriorly broadened, anteriorly narrowed. The wing bones are flattened in 
accordance with the usage of that limb, while the tarsal bones are very short and 
not perfectly fused together, as in most other birds, and again the pelvis shows 
unique features. The carotid arteries are two in number and the syrinx is tracheo- 
bronchial, tending to the complete bronchial form. The digestive system is very 
specialised, of the orthoccelous style, but quite unlike that of any other group, though 
suggesting those of the Pelecani and Procellarii. The ceca are small. The muscle 
formula of the leg is ABX-+, while the biceps muscle is absent, a feature restricted 
entirely to this group. The oil gland is present and tufted, while the aftershaft is 
present, though the feathers are so peculiarly adapted. The pterylosis is considered 
to be continuous though little research has yet been performed in this direction ; 
the nestlings are down covered. The antiquity of the members of this subclass is 
proven by the recovery from the Tertiary deposits of New Zealand of fossil remains 
which show the distinctive features of the recent birds to have been possessed at 
that epoch. The wings were longer but similarly adapted and the tarsal bones were 
imperfectly connected even as now. More recently extensive remains have been 
found in Patagonia and the Antarctic adjacent, many generic forms having been 
named but all obviously Penguins. 
OrpER SPHENISCI. 
Susorper SPHENISCIFORMES. 
Famity SPHENISCIDA, 
As Australian members of the family we have only Ludyptula and Eudyptes, 
the typical Spheniscus being confined to South Africa and South America. The 
two former range to New Zealand where also Megadyptes is found. All are gifted 
with short stout bills, the first named without any head ornaments, Megadyptes 
having the crown full and semi-crested, while Hudyptes has long tufts of flowing 
feathers on the sides of the head, the crown also full. Anatomically the evolution 
is considered to have paralleled the crest growth, and Spheniscus, which has also 
no crest, is ranked on about the same level as Hudyptula, though they represent 
divergent types. It may be noted, through the confusion of generic types, Budyptula 
was referred to Spheniscus with which it has little direct connection, and is the 
living representative of the immature state of Hudyptes. 
Genus EUDYPTULA. 
Eudyptula Bonaparte, Comptes Rendus Acad. Sci. (Paris), Vol. XLII, p. 775, May 1856. 
Type (by monotypy): Aptenodytes minor Forster. 
