176 THE SILURIAN TRILOBITES OF NEW SOUTH WALES, 



species is C. ornata, Hall,* from the Hamilton Group of New 

 York State, in which the thickened edge of the pustulose anterior 

 border is granular-crenate without being fimbriate. 



We have named the species after Mr. Joseph Horan, who has 

 been the companion of one of us on many pleasant excursions. 



Loc. (& Horizon. — Bowning Creek, Bowning, Co. Harden — 

 Lower Trilobite bed; Belle Vale, near Bowning, in the Lower 

 Trilobite bed ; and on Great Southern Road near cemetery, 

 Bowning— Middle Trilobite bed, Bowning Series C? Wenlock). 



All the specimens figured are from the Lower Trilobite Bed, 

 Bowning Creek (Coll. Mitchell). 



Cypiiaspis rotunda, sjo.nov. (PI. vi. figs. 2, a and b). 



Sp. Char. — Body oval. Cephalic -sliield subsemielliptical, pro- 

 })ortionately large, the axial measurement equal to that of the 

 thorax and pygidium combined, whilst the width is equal to its 

 own axial measurement and that of the thorax combined ; limb 

 wide, and concave in front of the glabella, margin thickened. 

 Glabella ovate, short, a pair of glabellar furrows (probably the 

 median) faintly indicated; circumscribed lobes small, oval, oblique 

 in position, very slightly truncate behind ; axial furrows moder- 

 ately defined in front, and continuous round the glabella ; facial 

 sutures anterior to the eyes tolerably straight, or slightly inclined 

 outwards, thence incurving along the thickened edge of the limb, 

 and cutting the latter in a line with the sides of the glabella, 

 whilst posterior to the eyes the sutures curve outwards, cutting 

 the posterior margin of the shield at about one-third the distance 

 between the axial furrows and the lateral margins ; fixed cheeks 

 small ; free cheeks large, tumid, with a wide limb, flat and striate; 

 genal angles produced into strong spines, which embrace the first 

 three thoracic segments ; neck furrow wide ; neck ring narrow, 

 moderately arched backwards. Thorax of eight segments, the 

 transverse measurement being about twice the axial length ; axis 

 prominent, width nearly equal to that of the pleurae, segments 



* Pal. New York, 1SS8, p. 490, vii, t. 21, f. 1. 



