Various forms of Cetacea have been met with in the four upper beds of the Miocene strata of the Maltese group. The discovery there of teeth of Zeuglodon by Scilla, and the abundant remains of one or more species of Dugong allied to recent forms and Balœnœ, show the prevalence of these mammals in the seas of the period. They are met with in the greatest numbers in the sand-bed and nodule-bands of the Calcareous Sandstone. In the latter situation I lately discovered a tooth which appeared to me to belong to the Halitherium , and in the sand-bed an ear-bone and caudal vertebræ of possibly the same genus. The tooth and ear-bone I have shown to Professor Owen, who has confirmed their identity with the above-named genus. The molar, possibly a penultimate, has lost one of its fangs. The crown is encased in thick shining enamel, and is 9 lines in length by 8 lines in breadth; the height of the crown is 2·6 lines. The fangs are two in number; the anterior small, the posterior large and diverging. The length of the latter is 7·5 lines. The accompanying sketch represents the crown (nat. size), which probably shows a more advanced state of wear than any figured by Cuvier. The ear-bone is entire, and measures 1·4 inch in breadth, by 9 lines in vertical diameter. The specimens referred to in this note are in the Musuem of the Geological Society.