that the characters upon which Professor Owen founded the 
species were merely individual. Xow, if this were true, the chances 
against another specimen being discovered possessing these 
characters are enormous. Yet our second Xototherium, recovered 
from a drained swamp in King Island, reproduces typically the 
very characters that Professor Owen founded his species upon! 
The information yielded by a study of these bones establishes 
two points of some importance to us, viz.: 
( i) That by the commonly accepted standards of classification 
Professor ()wen's taxonomy was sound in the creation of this 
species: 
(2) That in dealing with the classification of the extinct 
Xototheria we now have a limit to the value of individual varia¬ 
tion. and anything as pronounced as the characters of X. victorise 
cannot be fairly ruled out as individual variations. 
As it is outside my present purpose to continue this subject,. 
I shall only say that any characters claimed by me for the species 
tasmanicum are more pronounced than those hitherto ruled out 
as individual variations in the instance of Xototherium victorise. 
FEMUR. 
Professor (Even's type skeleton of Xototherium mitchelli did 
not include a femur among its fossil remains; but five years after 
his description appeared a distal end of one came to hand, and its 
characters were duly detailed in the Journal of the Geological 
Society. This bone included the distal condyles, and as much of 
the shaft as went to make up a total length of 216 mm., and in 
dealing with the complete femur I shall call this point of the shaft 
“ ()wen’s line." 
The femur of Xototherium tasmanicum has a fairly smooth 
shaft, almost completely oval in section, and quite unlike that of 
X. mitchelli (see comparative outlines). The head surmounts a 
short neck set at an angle to the main shaft of 40 degrees, and 
is so absolutely round as to give equal diameters in all directions. 
The trochanter major gives expansive surface for muscular attach¬ 
ment. and is pierced by an oval trochanterian fossa. 51 mm. x 
32 mm. in size, penetrating the bone (at an angle of 20 degrees 
to the centre of the shaft) to a depth of 38 mm. The second and 
third trochanters are indicated by cicatrices, the latter being an 
oval scar 50 mm. x 40 mm. Distally—and therefore comparatively 
—the ecto and ento-condyles are larger than those of X. mitchelli, 
while the intercondylar fossa is less extensive. The condyles also 
* Journal Geo. Society. Aug., 1882. page 394. 
