654 siLURLVN trilobitp:s of nkav south wales, v., 



eriimeiit Geologist. In the blue-grey schistose rock of both 

 Heazelwoocl, County Russell, and Zeehan, County Montagu, 

 occui's, amongst other trilobites, one referred to Cromus niur- 

 rhisoni, De Koninck,* but which can no longer be admitted as 

 this species or even geiuis. There were the larger portion of a 

 cephalic shield and four pygidia. The former is certainly of the 

 type of E. .s live rd( density, nobis. 



iv. NEW SOUTH WALES. 



Species admitted and described. 



In New South Wales, Encri^iurus is confined to beds of Upper 



Silurian age in the Upper Murrumbidgee Valley, at Delegate, 



and in the upper reaches of the Tarlo River, County Argyle. We 



are not aware of its occurrence in any other portion of the State. 



The Species admitted by us are: — 



Encrinurus mitchel/i, Foerste. 

 E. how7iingensis, Foerste. f 

 E. silver dalensis, nobis. 

 E. etheridgei, Mitchell, 

 E. rothivellce, nobis. 

 A'. dunfA'oonensis, nobis. 

 Besides the above species, several cephalons and pygidia are 

 described and figured ; but to which we refrain at present to give 

 specific names. 



k V. SOME STRUCTURAL FEATURES. 



Thei'e are a few^ structural matters we wish to refer to in par- 

 ticular, two of which we at first thought might prove to be of 

 generic importance, but although they do seem to occupy this 

 position in Australian forms of the yeiius, there is not the same 

 community of structure in foreign species. In every instance 

 examined, there are constantly five pairs of primary tubercles 

 along the axial edge of the glabella irrespective of any similar 

 tubercles which may occur in a like position on the neck-ring. 

 In testaceous specimens, these are but little seen; on the other 

 hand, in non-testiferous, or decorticated ones, they become a very 



* Etheridge, p. xliv., PL. figs. 7 and 8. 

 t Emended from Browningi, as writteu by Foerste. 



