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XIL Evidence of a large extinct Monotreme (Echidna Pamsayi, Ow.) from the 
Wellington Breccia Cave, New South Wales. 
By Professor Owen, C.B., F.P.S. 
Received November 3,—Read November 15, 1883. 
[Plate 14.] 
Amongst the detached bones and fragmentary evidences of Mammals from the above- 
named locality, submitted to me by Edward P. PtAMSEY, Esq., F.L.S., who thence 
obtained them, was a humerus sufficiently complete to yield the following characters. 
It was of great breadth in proportion to its length, and, through the unusual size and 
direction of the processes and ridges for muscular attachments, seemed as if the shaft 
of the bone had been twisted half-way round on its axis. 
The head, or proximal articular surface (Plate 14, fig. 1, a, and fig. 3), is a trans¬ 
versely elongated convexity, of a narrow ovate shape, with the broader end toward 
the ectotuberosity, h —the direction.of such joint being at right angles to that of the 
feline humerus, in which, as in Thylacoleo, the antero-posterior or then-anconal 
diameter prevails. The noil-articular portions of this end of the bone extend for 
equal distances to the ento-c- and ecto-6-tuberosities. From the latter is continued 
the “deltoid ” or “anterior bicipital” ridge, f from which, after its course of more 
than one-third the length of the shaft, it is continued by a lower ridge along the 
thenal aspect to be lost in the bony bridge overarching the neur-arterial canal, Jc, o. 
From the ento-tuberosity, c, is continued the “teretial” or “posterior tricipital” ridge, 
along the radial border of the humeral shaft to its termination in a special process 
— the “tricipital,” d. Moreover, both ento- and ecto-tuberosities are connected 
together by a low curved ridge or rising which bounds a small portion of the palmar 
surface of the shaft immediately below the head of the humerus. From the bridge, 
k, is continued a narrow ridge to the ent-epicondylar process, i. The distal end of the 
humerus is continued, ridge-like, from i to a process j midway between the epicon- 
dyles, h and if but bounding the ulnar trochlea, u. A notch below the outlet of the 
* In anthropotomy the term “condyle,” rightly applied to the prominent articular convexities of the 
“occipital,” “ mandibular,” and “ femoral ” bones, is transferred from the distal articular prominence of 
the humerus to the processes for attachment of muscles above the joint-surfaces. I have found it con¬ 
venient, in comparative osteology, to indicate the homologues of the “ external condyle ” and “ internal 
condyle ” of the human humerus by the terms “ ectepicondyle ” and “ entepicondyle.” 
MDCCCLXXXIV. 2 N 
