PALiEOMASTODON PARVUS. 
1G5 
M. 8889. 
C. 8063. 
M. 8890. 
seen that the deltoid ridge (d.) formed a prominent ohlicpie crest continued np to tlic 
greater tuberosity. The coronoid fossa (c.f.) is wide and moderately deeply concave; 
the olecranon fossa is large and deep, particularly on the outer side. The outer and 
inner (i.c. and o.c.) condyles are both fairly prominent, the latter projecting consideraldy 
backwards. The supinator ridge (s.r.) is short, much shorter relatively than in the 
humerus of F. headnelli dcscril)ed above. The articular surface is divided by a broad 
groove into an inner larger (fr.L) and an outer smaller portion (tr.o.). The former 
bears a slight ridge which marks the separation of the surface for the radius from 
that for the inner portion of the ulna. The bone, as a whole, is very thin-walled and 
lightly built — a circumstance that may account for the extreme rarity of bones of 
Palceomastodon. The chief points by which this humerus differs from that of Eleplias 
are : (1) the greater tuberosity is larger and rises more above the head ; (2) the 
supinator ridge is very much smaller, so that the distal portion of the bone is less 
expanded. 
Plaster cast of the above specimen. 
A similar right humerus wanting the proximal end. 
Plaster cast of the above specimen. 
Made in the British Museum. 
Made in the British. Museum. 
The dimensions (in centimetres) of the above humeri are : — 
C. 8881. 
C. 8063. 
Length 
. . . 45-2 
43-3 -f 
Width of head 
... 9 
. . 
„ of shaft at narrowest . . . 
... 5-7 
5*4 
„ lower end at widest . . . 
. . . 13-8 
13 + 
„ distal articulation .... 
... 9-8 
10 
C. 8028. Nearly complete right ulna (text-fig. 57) . The olecranon (pi. ) is large, greatly expanded 
at the end, and projecting strongly towards the inner side ; it does not rise above the 
upper angle of the articulation. This latter is triradiate in form ; the upper lobe 
projects strongly forwards, while of the lower two, the outer has a straight anterior 
border, beneath which is the elongated facet (r.s.) for the upper end of the radius; 
the inner is oval in outline and seems to have little or no contact with the radius. 
The whole shaft of the bone is curved backwards ; it is triangular in section, the anterior 
face being deeply' concave from side to side near its upper end (r.g.) Distally it 
widens out somewhat, but the epiphysis having been lost, the distal articulation cannot 
be described. The whole ulna is practically that of a miniature elephant. The 
dimensions (in centimetres) of the specimen are : — 
Length (without epiphysis) 38 
Width of articulation for humerus 9 3 
„ middle of shaft 4’8 
M. 8891. Plaster cast of the above specimen. Made in the British Museum. 
II. 8858. Upper end of left ulna. Presented by the Egyptian Government, 1904. 
C. 8883. Right tibia (text-fig. 58). In form this bone is almost exactly similar to the tibia of 
P. headnelli figured on PI. XVI. fig. 4. In the proximal articulation the inner facet (i.) 
