572 Fossil Molar Tooth of a Mastodon Aastralis. 



which Mr. Darwin saw at the same date. This Alga was again seen 

 many days running. Some specimens of it having been brought to 

 Dr. Hinds, he perceived that a penetrating odour escaped from it 

 which had before been thought to come from the ship; this odour 

 much resembled that which exhales from damp hay. In April 1837, 

 the Sulphur being at anchor at Libertad, near St. Salvador, in the 

 Pacific, Dr. Hinds again saw the same Alga. 



" A land breeze drove it for three days in very thick masses about 

 the ship. The sea exhibited the same aspect as at the Abrolhos 

 Islands, but the smell was still more penetrating and disagreeable ; 

 it caused in a great many persons an irritation of the conjunctive, 

 followed by an abundant secretion of tears. Dr. Hinds himself ex- 

 perienced it. The Alga in question constitutes a distinct species of 

 the genus Trichodesmium, and is named by M. Montagne T. Hindsii. 

 It differs from that of the Red Sea both in dimensions and smell." — 

 Comptes Rendus, \bth July, 1844. 



Description of a Fossil Molar Tooth of a Mastodon discovered by 

 Count Strzlecki in Australia. By Prof. Owen, F.R.S. 



The large fossil femur, transmitted to England in 1842, by Lieut. 

 Col. Sir T. L. Mitchell, Surveyor- General of Australia, from the 

 alluvial or tertiary deposits of Darling Downs, and described in the 

 'Annals of Natural History' for January 1843, p. 8. fig. 1, gave the 

 first indication of the former existence of a large Mastodontoid 

 quadruped in Australia. 



The portion of tooth described and figured in the same communi- 

 cation (p. 9. figs. 2 and 3), presenting characters very like those of 

 the molars of both the Mastodon giganteus as well as of the Dinothe- 

 rium, and being from the same stratum and locality as the femur 

 with which it was transmitted, was regarded by me as having most 

 probably belonged to the same animal ; and, on the authority of 

 drawings subsequently received from Sir T. Mitchell, was referred to 

 the genus Dinotherium* 



Having since received specimens of portions of lower jaws with 

 teeth identical in structure with the fragment figured in my first 



* Annals of Natural History, May J843, p. 329, fig. I. 



