434 DR. E. C. STIRLING ON THE [Nov. 5, 
The literature bearing on these and other allied points has been 
concisely summarized by Messrs. Lister and Fletcher in the ‘ Pro- 
ceedings’ of this Society for 1881, p. 977. These authors also 
there record a condition of patency of the aforesaid opening in 
some species in which its existence had not been previously noted. 
I observe that while ‘‘no one as yet seems to have had the good 
fortune to find an embryo in any part. of the vaginze,”’ Messrs. Lister 
and Fletcher nevertheless come to the following conclusion, which I 
quote:—‘ In the very early condition of the Macropodide the 
median canal is closed.” Again they say :— 
“<In some genera, viz. Macropus, Halmaturus, Petrogale (Dorcopsis 
and Dendrolagus ?), ari opening is formed in the median canal to give 
passage tothe young. This may take place in early life (Halmaturus), 
or not till young are about to be produced (Macropus). In the 
species Macropus major, however, this opening may or may not 
exist, and the young may be transmitted either through the median 
or the lateral canal.” 
For one species of Kangaroo, at least, this question of the route 
taken by the embryo may be considered settled, for I have been for- 
tunate enough to obtain a specimen of the female organs of Osphranter 
erubescens, Scl., which contain the embryo in course of transit along 
the passages. 
The organs in question, having been extracted by unskilled hands, 
were somewhat mutilated in the process, and further the operator, 
a cook in the camp of rabbiters, being a man of some intelligence and 
himself curious on the subject of marsupial parturition, had commenced 
an examination on his own account. These circumstances answer 
for the fact that the specimen is not anatomically complete, the 
lower part of the right lateral canal, a sinall part of the lower extremity 
of the left, and almost the whole of the urogenital passage having 
been cut away or left behind in the process of extraction. In the 
partial examination to which the specimen had been subjected before 
it came into my hands, the median canal had also been partially 
slit up from the front ; and in view of existing incisions I found it 
convenient to continue the dissection from this side instead of from the 
posterior (dorsal) aspect, by which the parts can be more satisfactorily 
displayed. Fortunately the essential parts and their relations to 
one another had not been disturbed, and the following is a brief de- 
scription of the specimen, represented in the accompanying drawing 
(fig. 1, p. 435) of about four fifths of the natural size. 
The embryo, closely enveloped in a thin amnion, was 11, 6, 
and 5 mm. in the long, antero-posterior, and lateral diameters re- 
spectively ; its anterior extremities distinctly five-partite, and the 
posterior distinctly three-partite and smaller than the anterior. The 
eyes just discernible as dark rings. It was suspended by a cord, 
which was extremely attenuated for some little distance from its 
point of attachment, though on unravelling this it was found to be 
distinctly membranous even at its thinnest part. The exact method 
of attachment of the cord to the body of the embryo cannot be 
stated with exactitude in this specimen, owing to the laceration which 
