PART 3.] 
Theobald: Axial group in Wcsleru Frame. 
81 
of the Bassein river, within the area of the Hill-rocks. At first this limestone seemed as 
devoid of fossils as most of the similar outcrops of the rock within the hills examined by 
me, but in one place I was rewarded by finding numerous small nummulites in it, which 
seemed to have escaped the molecular action, which, I presume, is the true cause for the 
general disappearance of fossils in the rock, and not its originally azoic character. Having 
thus satisfied myself that the “ Hill-rocks ” of Blanford comprising the southern portion 
of the Arakan range woro of Nummulitie age, and consequently distinct from the Axials 
of the Prome district, it became necessary to retrace my steps in order to discover where, 
in following down the line of altered rocks, I had, as it were, got shunted off the Axials on 
to the Nummulities. This point was very soon ascertained. The upper Axials, which are 
so well displayed on the frontier, hold their course continuously to within a short distance 
of the Thanni Cheung, a distance of forty-seven miles as the crow flies, from where they 
enter British territory, or a little above the parallel of Prpme. A few rolled lumps of the 
characteristic grits of the upper Axials may bo seen in the Thanni Choung, below the junction 
of a small stream, (the Thaybew Choung, not on map); but nowhere else can any evidence of 
the presence of this group he detected in the Thanni Choung, either above or below this spot. 
The upper Axials indeed stop here abruptly ; for, a very short distance up the Thaybew Choung 
the characteristic axial limestone comes in, from which I obtained numerous specimens of an 
ecluuoderm, unfortunately none of them in a state for identification. Thus far the boundary 
of the group is, I believe, a faulted one, hut here the fault would seem to die out and tho 
group to he covered up by the altered Hill-rocks of Nummulitie age. The rocks actually seen 
in the Thanni Choung do not give much assistance towards determining the question of their 
age. Just below the junction of the Thaybew Choung the shales are seen which may con¬ 
fidently he referred to tho Nummulitie group. Above the junction of the Thaybew Choung 
great disturbance and alteration of the beds is seen ; harsh indurated sandstones, vertical and 
much shattered and disturbed, occur, and above this spiot, sandstones and shales of the 
ordinary kind met with among the Hill-rocks. Now, for any direct evidence to the 
contrary, these might belong to either group; and their position is quite such as woidd 
identify them with the group of similar character underlying the upper or typical Axials. 
Thirty miles south of this is the village of Chin-na-gyec, where, in my note on the Axials, I 
thus described the boundary which 1 then supposed was tho junction of the two groups, and 
tlie continuation of that which in reality stops short of, and without crossing, the Thanni 
Choung. “ The stream above Chin-na-gyee seems to display mostly shales of the lower group, 
and just south of the village in the bed of the stream, highly altered sandstones come in of 
tho usual harsh character of so many beds belonging to this portion of the group. Not 
thirty yards below them comes in, quite unaltered, a calcareous sandstone profusely charged 
with nummulites. The boundary is here fixed within a few yards, and strikes through 
the centre of Chin-na-gyee village, and at this point would seem to completely cut out tho 
whole upper group” (of Axials). This section is merely a better and more sharply defined one 
than usual of the ordinary junction of the altered or Hill-rocks with the unaltered Num- 
mulitics ; and at the time I first visited it, I had no doubt of its being tho faulted boundary 
of the two groups (Axials and Nummulitios), instead of merely the boundary of that peculiar 
metamorphism which characterises the Hill-rocks, and which, the further we go south, 
seems more and more capriciously and irregularly developed. Of the lower Axials, now 
that all the Ilill-roeks to the south are separated from them, we know very little. The 
country occupied by them being, without any figure of speech, most impracticable. From 
the point near the Thanni Choung, where the group terminates, the boundary recedes to 
the westward along the watershed separating the Thanni Chouug from tho Muday Choung 
to the north. This is indicated in the map by a dividing range, which gives a very 
inaccurate conception of the physical aspect of the country, though it may, very pro¬ 
bably, correctly enough mark the actual watershed. Nattoung, a conical hill capped 
