204 
THE GEOLOGIST. 
Trent. Blackwater. 
Greatest vertical height from centre of auditory foramen, the 
glabello-occipital line being horizontal 4'8 4"7 
Distance of auditory foramen below glabello-occipital line . . 0*8 0'7 
Greatest transverse diameter 5 "4 5 "65 
Transverse diameter at the lower edge of the coronal suture . 4*4 4"75 
Horizontal circumference 20'5 20"75 
Transverse arc from one auditory foramen to the o*her . . . 13'25 13*0 
Antero-posterior arc from glabella to occipital protuberance . 12'5 12'5 
Antero-posterior arc from glabella to posterior edge of the oc- 
cipital foramen 14"25 14'4 
The plane of the occipital foramen of the Blackwater skull how- 
ever is less inclined, so that this feature may be accidental in the 
Trent skull. The frontal sinuses are also less developed in the Black- 
water skull, but in all other respects the resemblance is very close. 
The other Blackwater skull and one of the Nore skulls are also very 
like the Trent skull, but the remaining Irish skull from the Nore is 
much larger (having a length of 7*8 inches) and more depressed. It 
exhibits in a very marked manner, however, the projection of the su- 
perior part of the occipital bone beyond the occipital protuberance 
which characterizes the other skulls, and it retains a strong resem- 
blance to them in its other peculiarites. 
The Trent skull was found associated with bones* of the Bos longi- 
frons, Groat, Eed-deer, Wolf, and Dog, so that neither on this ground 
nor on any other that I am acquainted with does there seem to be 
any good ground for assigning to it a date earlier than the historic 
or immediately prehistoric epoch. 
I have dwelt thus long upon the Trent skull because of its compa- 
ratively perfect condition, and because, so far as the imperfect condi- 
tion of the fragments (fig. 2) from Heathery Burn Cave allow me to 
judge, they appear to belong to the same race of rather small and 
lightly-made men, with prominent superciliary ridges and projecting 
nasal bones. The few animal remains associated with them are all 
of recent species, and I see no reason for believing them to be of 
older date than the river-bed skulls. 
* See 'Geologist,' vol. iv., 1861, pp. 246, 349, 415, and 495. 
