224 Venous System of Didelphys Marsupialis (L) 
the following may be mentioned: ‘The presence of veins in the adult of 
Didelphys which undoubtedly correspond to the posterior vertebral veins 
of the sauropsida (Part I, pp. 380-1, these veins have not yet been 
observed in the Australian marsupials) ; the course pursued in the adult 
by the V. cordis magna which is similar to that in birds (Part I, p. 375) ; 
the presence of a type of postcava in the adult of Petaurus taguanoides 
and Phalanger ursinus which is similar to that met with in placentals 
in which the posteava lies to the right of the aorta and is formed through 
a union of its ilae tributaries which takes place dorsal to the aorta; the 
presence of posterior abdominal veins in the embryo of Didelphys; the 
absence of an anastomosis in Didelphys, between the left umbilical and 
omphalomesenteric veins, to form a ductus venosus Arantii, as in pla- 
cental mammals. 
LITERATURE CITED. 
ALLEN, J. A., or1.—A preliminary Study of the North American Opossums of 
the Genus Didelphis. Bull. of the American Museum of Natural 
History, Vol. XIV. 
Bepparp, F. E., g5.—On the Visceral Anatomy and the Brain of Dendrolagus 
Bennettii. Proc. Zool. Soc. of London for 1895. 
Broom, R., 98.—On the Arterial Arches and Great Veins in the Foetal Marsupial 
Jour. of Anat. and Physiology, Vol. XXXII. 
HocHSTETTER, F., 88.—Beitrage zur Entwickelungsgeschichte des Venen- 
systems der Amnioten. I. Vogel. Morph. Jahrb., B. XIII. 
——— g2.—Beitrage zur Entwickelungsgeschichte des Venensystems der 
Amnioten. II. Reptilien (Tropidonotus und Lacerta). Morph. Jahrb., 
Bd. XIX. 
——— 93.—Beitrage zur Entwickelungsgeschichte des Amnioten III. Sauger. 
Morph. Jahrb., Bd. XX. 
——— 96.—‘Monotremen und Marsupialier” in Semon’s Zoologische For- 
schungsreisen in Australien, Bd. II, Lief. ITT. 
——— 03.—Die Entwickelung des Blutgefasssystems in Handbuch der ver- 
eleichenden und experimentellen Entwickelungslehre der Wirbeltiere, 
Lief. 14 und 15. 3 
Lewis, F. T., 02.—The Development of the Vena Cava Inferior. Amer. Jour. 
of Anatomy, Vol. I, No. 3. 
o4.—The Question of Sinusoids. Anat. Anz., B. XXV. 
Miter, A M., 03.—The Development of the Postcaval Vein in Birds. Amer. 
Jour. of Anatomy, Vol. II, No. 3. 
McCuiurg, C. F. W., 00, (1).—On the frequency of Abnormalities in connection 
with the Postcaval Vein and its Tributaries in the Domestic Cat (Fe- 
lis domestica). Amer. Naturalist, Vol. XXXIV, No. 399. 
——— oo, (2).—The variations of the Venous System in Didelphys virginiana. 
(Preliminary Account). Anat. Anz., Bd. XVIII. 
