144 
Shell elliptical, subcylindrical, perforate ; colour, the two latter 
whorls pale yellow, the former purple ; whorls 41, flattened, angled 
below the suture, the last exceeding the rest in length ; sculpture, 
last whorl encircled by live, the penultimate by three, wide flat- 
topped 1 yne, crossed longitudinally by tine striae; suture impressed; 
umbilical chink oblique, narrow ; spire obtuse ; peristome free, 
entire, ovate, expanded. Length 21, breadth 1 mill. 
Hab. The creek to the north of the Old Settlement. 
23. B. rams a vi, Brazier , 1889. 
Illustration. Brazier, Aust. Mus. Mem. 2, pi. 4, tigs. 15, 16, 
(reversed). 
Type. Australian Museum. 
Shell narrowly ovate, perforate; colour corneous; whorls 41, 
convex, the last two-thirds of the total length ; sculpture faint 
oblique striae ; suture impressed; spire obtuse; umbilical chink 
narrow oblique ; aperture obliquely ovate, effuse {below, angled 
above, peristome entire, slightly expanded and reflected. Length 
4, breadth 2 mill. 
Ilah. Running streams on the eastern flanks of Mt. Ledgbird. 
ON THE ORGANISM JMSCOLOURTNG THE WATERS 
OF PORT JACKSON. 
By Tiios. Wiiitelegge. 
[The following report on the discolouration of the waters of the 
harbour has been prepared by authority of the Trustees of the 
Australian Museum, at the request of the Commissioners of 
Fisheries for New South Wales. 
It is a preliminary report, and has already appeared in some 
of the Sydney daily papers. Mr. Wiiitelegge is still engaged in 
the investigation, and in the preparation of a paper on the 
subject. — En.] 
Australian Museum, 13th April, 1891. 
To Dr. E. P. Ramsay, F.R.S.,E , Curator. 
Sir, — I have the honour to report that, in accordance with 
vour instructions, 1 have visited various parts of the harbour, 
with the view of ascertaining the probable effects of the Peridinium 
