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and the ambitus rounded. The actinal surface is slightly rounded 

 and depressed to the actinostome. The interambulacral areas are 

 twice the width of the ambulacra at the ambitus, and about one- 

 third broader at the mouth. They are slightly depressed in the 

 middle by an undulating line of suture which becomes a very 

 distinct depression on the abactinal surface, on which the lines of 

 the plates are well marked. The pores are in a vertical row, 

 slightly oblique, and their zones sunken. The interambulacra 

 have two rows of primary tubercles, each row being flanked again 

 on each side by a vertical row of secondaries, all small imperforate, 

 both primaries and secondaries surrounded by circles of granular 

 tubercles, which are frequently connected with the main tubercle 

 by a ridge. Ridges which are granular also separate the pores. 

 The primaries of the ambulacra are in two vertical rows, each 

 close to its poriferous zone. Their secondaries are not so visible, 

 but the rings of granules are very manifest, with an indented 

 vertical line of suture in the centre. Actinal opening large, 

 with conspicuous but not deep indentations. Diam. 16, alt. 6 

 millimetres. The specimen had been slightly crushed by pressure 

 so that the coronal plates were often disarticulated. 



This genus is very well represented in the tertiaryj rocks of 

 Great Britain, but principally I believe as a Pliocene form. 

 D'Archiac and Haime have figured from the Nummulitic formation 

 of India, a number of species which Agassiz (Revision of the 

 Echini) regards as belonging to this genus, Temnechinus. One 

 is found living in the American seas at a depth varying from 30 

 to 100 fathoms. The nearest affinities are T. globosus, of the 

 British Crag. 



From the evidence afforded by these fossils, and from a cursory 

 examination of the mollusca, I should not be inclined to regard 

 those beds as so old as those of the Murray River, Mount 

 Gambier, or Cape Otway. If we consider the Mount Gambier 

 beds as middle miocene, though there are strong reasons for 

 placing them even lower in the series, we may look upon the Yule 

 Island formation, from which these fossils were taken, as Lower 

 Pliocene. It is a most interesting fact to find evidence of recent 



