252 MR. W. P. PYCRAFT ON THE MORPHOLOGY AND 
Struthio is remarkable in that, according to Beddard, the right and left lobes are 
fused into a single heart-shaped lobe. There isa Spigelian lobe. The gall-bladder 
is wanting; and there is but a single bile-duct, which opens near the pylorus. 
Mr. Beddard found the free edge of the liver in Rhynchotus rufescens pierced by 
three small vessels of the venal portal system—a fact which, as he points out, has a 
very lizard-like appearance. 
RESPIRATORY ORGANS. 
a. THe Lunes (Pl. XLV. fig. 9). 
The costo-pulmonary muscles in Caswarius aré short, thick, and powerful, five pairs 
in all; they arise from the thoraco-sternal articulation of the ribs and extended fanwise 
on to the aponeurosis covering the lung. Those of hea are relatively longer than in 
Casuarius. In Apteryx, according to Huxley [41], they form “ broad flat bands,” which 
“take their origin from the vertebral ribs, at some distance below the attachment of 
the pulmonary aponeurosis, and, proceeding obliquely dorsad and forwards, spread 
out and are inserted into that part of the aponeurosis which covers the posterior 
inferior facet. 
In the relative size and distribution of the ecto-, ento-, and para-bronchia, and in the 
size of the vestibule, the flightless members of the Palwognathe do not appear to 
differ much one from another or from the Neognathe. 
In the lungs of a Caswarius wnappendiculatus the bronchial rings extended backwards 
as far as the 4th ento-bronchium. ‘The inner border of the anterior and posterior 
inferior facets of the lung are deeply sculptured by a system of numerous parallel 
grooves of open tubes, closely packed and running along the surface of the lung from 
the mesial border outwards so as to converge towards, and open into, a spacious 
chamber communicating posteriorly and ventrally with the Ist ento-bronchium 
(Pl. XLV. fig. 9), further forwards and also ventrally into the anterior end of the 
pre-bronchial ostium. These grooves give the ventral face of the lung, after the 
removal of the aponeurosis, the appearance of having been bored by Teredos, the groove 
representing a hemisection. ‘They are crossed and recrossed by transverse strands of 
tissue and punctured by minute apertures. 
They may be divided into two groups according to whether they are fed by a trunk 
from the Ist or the 3rd ento-bronchium. Thus, as will be seen in fig. 9, all the 
secondary grooves cephalad of the main trunk marked “ent. 1.” are fed from this, whilst 
ento-bronchium I. supplies all the grooves caudad thereof. 
These grooves are converted into tubes by the pulmonary aponeurosis. 
b. Tur Arr-sacs (Pl. XLV. fig. 8). 
In Casuarius the pre-bronchial sae is paired, and extends forward on each side of 
