As I have prepared descriptions of nearly all the fossils of Victoria collected by the Geological Survey under Mr. Selwyn for some years, I have been urged to make a preliminary publication in the Geological Magazine of some ofthe remarkable forms, and I now forward my descriptive note of the two Tertiary Trigoniœ, on account of Mr. Jenkins' paper in the May number of this Journal, in which one of them is referred to the recent T. Lamarckii. I feel assured that if Mr. Jenkins will look at the edge along the ribs, towards the beak of a recent specimen of T. Lamarckii and my T. acuticostata from the Tertiary beds, he will at once appreciate the distinctive form of the ribs which I point out and figure in the annexed woodcut.