4 H. J. Harman— Operations for obtaining [No. 1, 
number, the two upper long, narrow and adjacent, the 3rd is a flattened 
dome-like mass, the 4th is long and curving inwards. Behind this at a short 
distance is the second row, consisting of fourteen very minute, closely 
arranged, thin, longer or shorter tooth-like processes, those on the upper 
side being slightly the largest. 
Major diam, 0°35 ; minor diam. 0°32 ; alt. axis 0-2 inches. 
Hazs.—This very interesting new form was also obtained by Mr. Ogle 
near Brahmakhund, eastern Assam, at 1,000 feet elevation... 
The arrangement of the internal barriers is unlike any species of this 
sub-genus I have yet examined, and shews a decided departure from the 
usual North-East Frontier forms, a sort of foreshadow that in the mountains 
further east this particular development is to be found of a like or more 
marked character. 
In external form the present species resembles P. shiroiensis, but may 
be distinguished from it by the coarser epidermis and more regular striation, 
and the broader wider size of the last whorl near the aperture, shewing no 
constriction. It is of interest to note that the flattened dome-like barrier on 
the palatal or mantle side coincides with the vertical barrier in P. shiroiensis 
where we see the distinct result of two teeth fused as it were together. 
This species should come in after No. 18, P. refuga, var. dextrorsa, as a 
sub-section b’ of group B of the key in P.Z.S. Palatal vertical plice only 
compound, in two rows, numerous. Horizontal parietal amine short. 
OOO 
II.—On the Operations for obtaining the Discharges of the large Rivers in 
Upper Assam, during Season 1877-78.—By Lizvur. H. J. Harman, 
R. E., in charge Assam Valley Series, Survey of India. Communicated 
by Masor-Genu. J. T. Watxer, R. E., C. B., F. R. S., Surveyor 
General of India. 
[One of the Survey Operations during the field season of 1877-78 was 
to explore as much as possible of the region between the Subansiri and the 
Dihang Rivers, with a view to ascertaining which of these two afiluents of 
the Brahmaputra river had the best claim to be considered the recipient of 
the Sanpo River of Thibet. As there was reason to fear that political 
difficulties might intervene to prevent the survey officers from proceeding 
a sufficient distance into the interior to settle this disputed point, Lieut. 
Harman was directed to measure the discharges of the several rivers at 
various points, and to ascertain the volume of water in each river in order 
that additional evidence might be forthcoming on an interesting geogra- 
phical problem. The following paper gives the details of these operations. 
Jeo Ws] 
