BY K. ETHEiaDGE, JUNU., AND JOHN MITCHELL. 709 



and under the ocular ridges, passing out in a line with the outer 

 edges of the median glabella lobes, and cutting the margins at an 

 angle of about 25°. Free cheeks subtriangular or subcrescentic, 

 much expanded at the front lateral angles, fi-om thence to the 

 genal angles rather straight and inclining inwards, highly tul)er- 

 culate and rugose; genal sj^ine ridges strong, very prominent, and 

 ■vanishing under the eyes; borders distinct, strap-like, smooth and 

 entire: marginal furrows faint; genal angles almost in a line with 

 eyes, axiall}^ lieai-ing strong, suberect, long arching spines, which 

 will apparently reach to the fifth or sixth thoracic segment. 



Thorax. — Unknown in a complete state, probably consisting of 

 ten segments, and as wide as long ; very conspicuously tubei'- 

 culated and granulated, and flat. Axis very distinct, very 

 moderately arched vertically, ends of segments very distinctly- 

 separated from the central portion by furrows, strongly inclined 

 forwards, and with a very joint-like chai'acter, only moderately 

 tumid ; central portion of segments without backward ai'ch, each 

 segment bearing two prominent tubercles, one on either side, about 

 midwixy between the nodes and the central line ; articulating 

 surfaces very large, furrows distinct. Lateral lobes horizontal; 

 ventral ridges of the pleurae on the inner halves as wide as the 

 pleurae, thence contracting to the bases of the pleural spines and 

 leaving low grooved triangular areas on each side, of which the 

 antei'ior ones are the largest, they are furrowed alpng the central 

 line from the bases of the spines for about half of their length; 

 the interpleural furrows very deep and wide ; sutures distinct^ 

 straight and rectangular to the axis. Pleural bispinate, principal 

 or upper spines very long, barbed, and on the anterior pleurae 

 subhorizontal, and subrectangular to the axis, subarcuate with 

 reflected ends, posterior ones having sharply backward and upward 

 directions; posterior pair at least rising perpendicularl}' from the 

 pleurte with their extremities converging towards each other, and 

 oi-iginating some distance short of the extremities of the pleurai; 

 the secondary or inferior spines originate almost immediately 

 under the principal spines, ai'e stout, cylindrical, fleeted sharply 

 downwards and forwards at about 30° and barbed with acicular 

 47 



