58 Mamm. 
MAMMALIA. 
12 . MONOTREMATA. 
Klaatsh, H. Ueber die Beziehungen zwischen Mammartasche und 
Marsupium. Morph. JB. xvii, pp. 483-488. 
A discussion as to the relation of the depressions containing the 
mammae of the Marsupials and Monotremes to the marsupium, 
OrNITHORHYNCHIDJE. 
Stewart, C. On a Specimen of the True Teeth of Ornithorhynchus. 
Q. J. Micr. Soc. xxxiii, pp. 229-231, pi. viii. 
Describes and figures a skull, shoeing three teeth in position iu each 
jaw, thus proving the complete dental formula to be f . 
Symington, J. On the Nose, the Organ of Jacobson, and the Dumbbell- 
Shaped Bone iu the Ornithorhynchus. P. Z. S. 1891, pp. 575-584, 
pis. xliii & xliv. 
The anterior part of the nasal chamber is shown to be divided into 
three compartments by horizontal septa ,* Jacobson’s organ is described as 
being more developed tfyan in any other Mammal, and, indeed, probably 
more so than in Lizards ; while the “ dumbbell shaped ” bone is proved to 
be formed by the coalescence of the inner moieties of the premaxillae. 
INOERTiE ORDINIS. 
f Mesitotherium, Trouessart, 1883, adopted by F. Amegiiino to 
replace the later Macropristis , Amegh. [Zool. Rec. xxvi, Mamm. p. 55]. 
4 f Anantiosodon varus, n. g. & sp , Amegiiino, Rev. Arg. Hist. Nat. i, 
p. 327, Tertiary, Patagonia. 
