]\I(KKIT1IKIUIJM GRACILE. 
127 
Moeritherium gracile, Andrews. 
[Plate XVir. figs. 1-3.] 
l'.)02. Ma’vitheriuin (jrac'de, C. W. Andrews, Geol. Mag. [4] vol. ix. p. 292. 
Type Speeimen. — An imperfect skull (PI. XVII. figs. 1, 2), including the palatal 
region, associated with cervical, dorsal, and lumbar vertebrae ; Geological Museum, 
Cairo. 
I'his species is distinguished from M. lyonsi by its comparative lightness of structure, 
the narrowness of the palate, the smaller size of the upper molars and premolars, 
particularly of m. 3, the strong development of the cingulum in these teeth, and by 
the considerable inflation of the cranial region of the squamosal, which apparently 
contains extensive air-sinuses. 
Form. & Log. — Qasr-el-Sagha beds (Middle Eocene) : north of Birket-el-Qurun. 
C. 10003. Cranial and palatal regions of skull with some vertebras. Type specimen described in 
Geol. Mag. [4] vol. ix. p. 292. Figured on PL XVII. figs. 1, 2. The palatal portion 
(fig. 1) shows very well the great enlargement of i. 2, the extension forwards of the 
maxilla (»ur.) beneath the premaxilla (ptux.), the presence of a median anterior palatine 
vacuity, the relatively small size of the teeth, particularly of the third molar (m. 3). 
The cranial region (fig. 2) shows the comparative narrowness of the supraoccipital 
escutcheon (soc.) (cf. PI. X. fig. 4 a) and the inflation of the upper part of the 
stpiamo.sal (sq.). The dimensions (in centimetres) of this specimen are : — 
Distance from anterior end of snout to hinder border of palate . 21 
Width of palate o^^posite 2 2'8 
Approximate width of supraoccipital escutcheou 8‘G 
Total width of occipital surface 18‘6 
The dimensions of the teeth are : — 
Length. Width. 
2^m. 2 2-2 1-8 
2)m. 3 2 2'3 
2ml. 4 2 2-1 (?) 
m. 1 2-3 2-3 
7)1. 2 2'4 2’5 
m. 3 2-8 2-4 
Length of molar and premolar series 13-7. 
Length of molar series 7'5. Length of premolar series 6’2. 
The vertebrae belonging to this skull include the centra of the axis and the five 
posterior cervicals (two having part of the arch preserved), an anterior dorsal with part 
of the arch, also five other dorsal and two lumbar centra. 
The form of the axis, so far as it is preserved, is similar to that of the axis of 
4/. hjonsi. The centra of the posterior cervicals are oval in outline and slightly 
