BY R. ETHERTDGE, JUNR.^ AXD JOHN MITCHELL. 663 



Thorax. — Length approximately two-thirds of the width; axis 

 strongly arched, of uniform width to the eighth annulation, the 

 three remaining ones narrower; all the annulations tuberculate 

 at their bases, and granulate along their medial lines; pleural 

 segments wider than the axis, moderately geniculate, finely 

 granulate. 



Pyyidhuu widely triangular, relatively large, but bearing no 

 constant ratio to other parts of the body; axis moderately pro- 

 minent, bearing twenty or more annulations, the first only con- 

 tinuous; median free area bearing usually seven or eight tubercles 

 of which five or six are prominent, yet not restricted to any par- 

 ticular annulations, but the second mostly bears one, pleural 

 lobes transversely convex, and as compared with those of the 

 thorax depressed, the segments increasingly inclined backwards 

 until the last pair, which are nearly parallel with the pygidial 

 axis. 



Ohs.—T\\Q cephalon of this trilobite, or rather a portion of a 

 cephalon, was described by Mr. Foerste from material supplied 

 by one of us. 



E. howyiingensis differs from the European E. pnnctatus in 

 precisely the same manner as does E. ndfcJielli, except that, 

 unlike the latter, it agrees with it in the shape and tuberculation 

 of the glabella. When examples of the two Australian forms 

 are compared, the differences are so obvious, and at once appa- 

 rent as to hardly need comment. The form of the glabella, 

 tuberbulation, outline of the pygidia, and the manner in which 

 the axial furrows traverse the free cheeks can be relied on for 

 separation, 



De Koninck's A\ harrandei, from Yarralumla, was compared 

 by Mr. Foerste wdth the present species, and his words referring 

 to the former are as follows: — "This-is evidently the most closely 

 related species, but if his [De Koninck's] is at all correct then 

 our species \_E. bowningensis] is quite distinct." Mr. Foerste's 

 specimen was devoid of eyes; had it not been so, De Koninck's 

 remark that these organs were only raised a little above the 

 surface in E. harrandei, his remark would have probably been 

 still more emphatic. 



