1896.] MR. F. E., BEDDARD ON DISSURA EPISCOPUS. 233 
Ciconia; and it may be possible to regard it as congeneric with 
Abdimia, remembering that: both are African in range. In any 
case we have here a distinct relation between structure and 
geographical distribution. ) 
The Storks and Herons are contrasted by other structures than 
those to which reference has already been made in the present 
communication. I desire now to call the attention of the Society 
to certain structures which have not hitherto been used in this 
connection, and which indeed have been but little made use of in 
the systematic arrangement of birds. These characters are drawn 
Fig. 2. 
Syrinx of Abdimia sphenorhyncha. 
from the number and position of the muscles of the lungs, those 
muscles which usually arise from the ribs and expand over the 
pulmonary aponeurosis. To the complete set of these muscles 
the term “diaphragm” has been applied. But at the present 
moment I am not concerned with their general morphology, but 
with their use in detailed classification. 
It has been stated by Prof. Weldon’ that in the Storks “ the 
pulmonary aponeurosis is not muscular.” So far as my experience 
enables me to say, that statement is nearly but not absolutely 
true. 
In a specimen of Ciconia alba I found a single muscle on each 
side of the body arising from the most anterior of the ribs bordering 
upon the lung, and lying just in front of the anterior intermediate 
air-sae. The rest of the pulmonary aponeurosis was perfectly free 
from muscles. On the other hand, the Herons are well provided 
~ ¥ “On gomé Points in the Anatomy of Phanicopterus,” P. Z. 8, 1883, p, 640, 
