Annals of the Transvaal Museum, 
73 
The Premaxillary. 
This bone has the same general shape as that of latirostris, but in 
detail it shows many peculiar differences. As in latirostris it is in contact 
with the nasals, the septomaxillaries, and the maxillaries. The sutures 
with these bones are, however, not clear. 
In latirostris the side-surfaces of the premaxillary make nearly a right 
angle with the upper surface. For comparison I have now ascertained 
that this angle is somewhat larger than sixty degrees. In Putterilli this 
angle is only thirty degrees. Thereby the skull of Putterilli acquires a 
much broader appearance, and this breadth is heightened by the relatively 
broader maxillaries. The proportion of the breadth across the maxil- 
laries near the oral edge in latirostris to that of Putterilli is as 9,5 to 15,5. 
The proportion of the length of a perpendicular from the middle of the 
oral edge on a line which connects the front ends of the maxillaries behind 
the teeth in latirostris to that of Putterilli is as 5 to 6,7. Compared with 
latirostris the breadth of Putterilli has augmented with 6 cm. and the 
length of the mentioned perpendicular only with about 2 cm. The pro- 
portion in latirostris of the cited dimensions is as 9,5 to 5 or nearly as 2 
to 1. The proportion of their increase in Putterilli is as 3 to 1. We there- 
fore see that in the skull of Putterilli, compared with that of latirostris, 
the breadth of the oral portion increases relatively more than the already 
mentioned perpendicular, which might be called the height of the snout. 
The central ridge on the premaxillary is very clear. The lateral 
ridges, however, are not so clear through the small angle between the 
upper surface and the lateral surfaces. This is especially the case near 
the oral opening where the upper surface curves without definite 
demarcation into the lateral surfaces. The lateral ridges are prominent 
above the external nares. 
There is a transverse ridge between the nares, where the sutures with 
the nasals appear on the upper surface (PI. XI). This ridge divides the 
grooves between the lateral and central ridges in two. An analogous 
feature has not been observed in latirostris nor in Mccaigi . 
As in latirostris the lateral surfaces bend sharply inwards at the 
nostrils. 
The general shape of the palatal surface (PL XII) is the same as that 
of latirostris. The acute angle which is formed by the front part of the 
palatal surface with the upper surface is, however, much more acute in 
Putterilli. In latirostris this is an angle of forty-five degrees and in Put- 
terilli it is one of only fifteen degrees ; it is nearly forty-five degrees in 
Mccaigi. 
Dimensions : 
Length of the upper surface ±135 mm. 
Breadth of the bone where the suture with the nasals 
enters the nostrils 39 5 mm. 
Mutual distance of the points where the sutures be- 
tween premaxillary, maxillary, and septomax illary 
meet under the nostrils ±56 mm. 
Distance of these points to the oral edge, measured along 
the suture with the maxillary 
70 mm. 
