1909. ] SUBDIVISIONS OF THE BODY-CAYITY IN BIRDS. 227 
entirely closed cavities, lying between the post-pulmonary and 
post-hepatic septa, the alimentary canal and the liver. The post- 
hepatic septum passes dorsal to and behind the liver-lobes, and 
ventral to and in front of the intestines, and carries on its ventral 
surface the right anterior abdominal vein. The gizzard is enclosed 
within its thickness, in the ventral portion of the septum, and is 
thus completely shut off from the ventral liver-sacs, the posterior 
walls of which are constituted by the anterior peritoneal layer of 
the sheath of the gizzard. 
This septum has been described in the Stork (Lepétoptilus) and 
the Flamingo (Phanicopterus antiquorum) by Weldon {17 |, and in 
Rhea, Struthio, and Dromeus by Beddard [1]. Inthe Struthiones 
the liver-sacs are said to be closed off posteriorly from the 
space ventral to the post-hepatic septum, and this may possibly 
be compared with the condition found in the Crocodilia (see 
below). Beddard also describes the septum in Cranes and Horn- 
bills, in the Penguin (Spheniscus demersus), in the Spur-wingerl 
Goose (Plectropterus gambensis), and in Bernicla brenta, where 
the septum bears a second (left) anterior abdominal vein which 
apparently corresponds to that occurring in reptiles, in the Grue 
(Cariama) and in many other birds; and I have myself observed 
it in the Golden Eagle. It probably therefore occurs throughout: 
the entire group. 
Ill. THe SrrRucTURES POSSIBLY REPRESENTING THE 
AVIAN SEPTA IN REPTILES. 
There are but few descriptions of the subdivision of the ecelom 
in the Reptilia, and these deal mostly with the adult anatomy ;. 
so that it is impossible to establish any homologies between these 
forms and Birds, in the almost complete absence of embryological 
evidence. I have therefore merely collected such facts regarding 
the subdivision of the ccelom in the various groups as may be of 
significance when more work on the development has been done. 
In the Lacertilia generally there is no representative of either 
the post-pulmonary or the post-hepatic septum, but in many 
genera — Lacerta, Iguana, Chameleo, and others—there is a 
well-developed pulmo-hepatic ligament, and consequently a pulmo- 
hepatie recess is formed on the right side [9]. This arrangement 
occurs again in Sphenodon, and is found of course also in 
Mammals [13]. In the Teiidee, however, Butler describes a well- 
developed post-hepatic septum in Z'upinambis teguexin, and a 
slight approach to this condition in Ameiva surinamensis and 
Callopistes maculatus, where the median ventral ligament is ex- 
panded laterally behind the liver, but does not become attached 
to the body-walls. In Zupinambis, however, the subdivision of 
the body-cavity into a pulmo-hepatic and an intestinal portion is 
almost complete except for a small aperture on either side. These 
are situated in the dorsal moiety of the septum, and hence Butler 
compares the latter with the ventral or omental part of the post- 
hepatic septum of birds; the absence of the dorsal portion in 
