In making an examination of some samples of Phosphorite, recently discovered in Southern Russia, I was much struck by the unusual appearance of the substance, and after a closer examination came to the conclusion that it was a new form of the mineral, and ought to be brought before the notice of this society, in order that its occurrence and physical structure might be recorded and discussed.

The mineral which forms the subject of this paper occurs in rounded masses, varying in size from 5 to 9 inches in diameter. The outer surface is smooth and presents an appearance highly suggestive of the form being due to the action of running water, but upon fracturing several of these balls I found in every instance that they were c6mposed of a number of fibres radiating from the centre, of small size, and of a blueish grey colour, having a hardness of about 4.