20 



the district for building purposes. It has been recognised at 

 various points within a radius of five or six miles from the 

 mouth of the river, and in some places shows a pre- 

 cipitous face of nearly 100 feet above high water mark. 

 Although there is no section visible showing the actual 

 contact between these beds and the basalt, which occupies 

 a large extent of the adjacent country, there is no reason to 

 doubt their priority to it; indeed, Mr. Hainsworth has 

 informed me of an instance where basalt is found capping a 

 small isolated hill which I know to have been formed by de- 

 nudation, and which the basalt could only have reached by 

 flowing in a lava-like sheet from a higher adjacent summit 

 before the denudation had commenced. It is, however, quite 

 possible that the fossiliferous strata represent two distinct 

 periods, and that a portion of those which appear to abut 

 against the basalt without the slightest alteration in character 

 or position, may one day prove to be of more recent date. 



The Museum already contains a series of these Tertiary 

 fossils, presented by different donors, but it is surpassed both 

 in extent and variety by the collection now before us. The 

 specimens are for the most part tolerably perfect, but some of 

 the more delicate shells were so injured by pressure upon the 

 decomposing matrix in which they were embedded that they 

 could not be cleaned for purposes of identification, and had to 

 be preserved in their rough state. The collection contains 

 upwards of sixty species of Mollusca, representing the follow- 

 ing genera : — Stromhus, Typhis, Fasciolaria, Cancellaria, Cassis, 

 FusuSj Ancillaria, Conus, JPleurotomaria, Voluta,Mitra, Oyprceay 

 Trivia, Natica, Fotamicles, Turritella, Siliquaria, Littorina, 

 Trochus, Dentalium, Terehratula, Waldlieimia, Mhynclionella (?), 

 Ostrea, JPecten, Lima, Spondylus, Modiola, Area, Limopsis, 

 Cucullcda, JPectunculus, Trigonia, Cliama, Cardium, Liicina, 

 Cyprina, Cardita, Venus, Venet^upis, Crassatella, Tellina^ 

 JBholadomya, Corhula, with a few others which I have not been 

 able to identify. The Echinida are represented by species of 

 Cidaris and SpatanguSj and there are also two or three species 

 of corals. 



Among the shells which are now extinct one of the most 

 noticeable is " Trigonia semiundulata'' (M'Coy). This shell has 

 not been found elsewhere in Tasmania, but I have seen it in 

 similar formations on the shores of Port Phillip. It is worthy 

 of remark that the recent Trigonia, of which we have two 

 representatives, has not been found at all in the Table 

 Cape beds. There is also a good specimen of a Cyprcea, which 

 is found nowhere else in Tasmania, and seems to be inter- 

 mediate between G. eximia and the recent G. umUlicata, both 

 of which are here found as Tertiary fossils. The collection 



