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more nearly allied to the “ Galli ” or to the “ Hemipodii,” because 
these two groups either agree with each other or the characters 
differ too much within the “ Galli ” themselves. 
Vascular and Respiratory System. 
Pedionomus possesses two carotides profun dse s. caro tides sub- 
vertebrales ; the left carotis is slightly weaker than the right and 
covers the latter ventrally. Pedionomus agrees in this respect with 
most (but not with all) Rasores, not necessarily however because 
of any close affinity with them, but because the presence of these 
two subvertebral carotids is an old, unchanged feature, which per- 
sists in most birds. In Turnix and in the Megapodidte there is 
one carotis-conjuncta, but the right root, i.e. the basal portion of 
the original right carotis, has been obliterated. It is not likely 
that this condition has been developed directly from that of 
Pedionomus , because in this bird the basal portion of the left 
carotis is slightly the weaker one, on the contrary it shows that 
Pedionomus has made an independent departure. The trachea is 
peculiarly flattened dorso-ventrally, as in the Ratitie. Its numer- 
ous cartilaginous rings are soft and very narrow. The Syrinx 
exhibits no specially remarkable features, it agrees in its compo- 
sition closely with that of Turnix and differs from that of the 
Rasores. The pessulus is very weak and there is no distinctly 
separated branchidesmus. The semi-rings of the bronchi surround 
the whole ventral surface of the latter. The voice is produced (1) 
by a pair of membranse tympaniformes internee, which from the 
pessulus onwards occupy the whole dorsal and median half of 
each bronchus, (2) by several pairs of membranse tympaniformes 
externee, the first of which is the largest and lies between the first 
and second semi-ring of each bronchus, while smaller membranes 
exist between two and two of the following semi-rings. The voice 
is moderated by two pairs of muscles. Each m. sterno-trachealis 
runs down from the larynx along the side of the trachea and is 
inserted on to the lateral anterior process of the sternum. Each 
m. tracheo-bronchialis begins at the point where the m. sterno- 
trachealis leaves the trachea, runs along its side and is inserted 
upon the middle of the first bronchial semi-ring. The whole syrinx 
is distinctly tracheo-bronchial. 
Alimentary System. 
Neither Turnix nor Pedionomus possesses a crop, but the upper 
half of the oesophagus is very dilatable. The gizzard is very strong 
and of a rounded-off rhombic shape,* without the marked con- 
striction on its upper anterior margin which exists in the gizzard 
of Turnices and Rasores. Turnix and Pedionomus agree however 
in having a slight indication of a pyloric stomach. The rest of 
the alimentary canal of Pedionomus forms three great loops. The 
* Contents : quartz pebbles, and several hard Colceoptera. 
