258 ON A TRILOBITE FROM REEFTON, N. Z., NEW TO AUSTRALIA. 



their surfaces are rubbed off. The facial suture is well marked, 

 but as the posterior angles of the shield are broken off, it is 

 impossible to say whether it ran out exactly at that angle or a 

 little in front of it. 



The Thorax is very indistinctly trilobed, and consists of thirteen 

 segments, all of which are more or less tubei-culose along a trans- 

 verse rib on the posterior half of each segment. There are about 

 seven or eight tubercles on the tergal portion of each segment and 

 several smaller ones on the pleurse. The tergal portion is smooth 

 and very finely pitted, but the anterior portion of each pleura is 

 coarsely granulated, resembling the granulations on the margins of 

 the free cheeks. The tubercles are irregularly placed. The length 

 of the thorax is rather more than four inches. 



Pygidium. — Six segments only remain, each has about ten 

 small tubercles on the tergal part and five or six on each pleura. 

 The surface is smooth, except towards the margin where there are 

 scattered granules. The margin itself is incurved and coarsely 

 granulated like that of the cheeks. Its length may have been 

 about an inch and a-half. 



This species very closely resembles, and is perhaps identical 

 with Honnalonotus Uerschelii (Murchison), from S. Africa, 

 described and figured by Mr. Salter (Trans. Geol. Soc. 2nd 

 Series, Vol. VII., p. 215, pi. 24, figs. 1-7). The differences appear 

 to be that our specimen is broader in proportion and the thoracic 

 segments are flatter and with more tubercles. However, until the 

 rostral and caudal portions are known it is impossible to give a 

 decided opinion on this point. At any rate it belongs to a group 

 highly characteristic of the Lower Devonian. 



