210 MISS M. POOLE ON THE DEVELOPMENT OF THE __ [ Mar. 2, 
The following papers were read :— 
1. The Development of the Subdivisions of the Pleuro- 
peritoneal Cavity in Birds. By Marcarer Poois.* 
[Received February 9, 1909.] 
(Text-figures 24-37.) 
The subject of this paper was suggested to me by Professor 
Bourne, and it was by his advice that I undertook a reinvestiga- 
tion of the development of the subdivisions of the body-cavity in 
birds; my object being to confirm and enlarge the results put 
forward in a paper on the subject by Mr. G. W. Butler in these 
‘Proceedings.’ At that time I knew of no other work on this part 
of the question; and it was only when IJ had almost completed my 
study of the development of these structures, that Mr. Beddard 
kindly referred me to the work of Dr. Bertelli. This I found was 
published in an Italian journal not—so far as I could discover— 
taken in by any of the scientific libraries either in Oxford or 
London ; and it was only by the very great kindness of Dr. Bertelli, 
who sent me a copy, that I was at last able to seeit. I then 
found that he had worked out and described in great detail and 
with admirable clearness, almost the whole of the development 
upon which I was engaged. But since this valuable paper is 
practically inaccessible to English students, Dr. Bourne advised 
me to publish the results of my own investigations, which I had 
arrived at independently. I may here state that my results 
entirely confirm those of Mr. Butler, and, except in two small 
points, those of Dr. Bertelli also. 
;: The work was done in the Zoological Laboratory at Oxford py 
the kindness of Professor Bourne, and I wish to take this oppor- 
tunity of expressing my warmest thanks to all in the Department 
—and especially to Mr. Goodrich—who have helped me by 
continual suggestions and advice. 
I wish likewise to express my gratitude to Dr. Bertelli for his 
kindness, not only in sending me a copy of his work, but also for 
his permission to make any use of his observations in my own 
paper. 
NOMENCLATURE. 
The pulmonary aponeurosis of Huxley [12] and Butler [9]— 
diaphragme pulmonaire of Sappey [16]—Bertelli [6, 8] calls the 
diatramma ornitico. 
The oblique septum of Huxley, employed by Butler, Beddard and 
others—the diaphragme thoraco-abdominal of Sappey—Bertelli 
does not consider to be a septum at all, but only the ventral walls 
of the intermediate air-sacs together with the posterior wall of 
* Communicated by Prof. G. C. Bourne, D.Sc., F.Z.S. 
