170 THE SILURIAN TRILOBITES OF NEW SOUTH WALES, 



Genus Cyphaspis, Burmeister, 1843. 

 (Organ, der Trilob. p. 103.) 



Cyphaspis bowningensis, Mitchell (PI. vi. figs. 3, Za-h ; PI. vii. 



figs. ?>i-k). 



Cyphasjns bowningensis, Mitchell, P.L.S.N.S.W. 1888, ii. pt. iii. 

 p. 418, t. 16, f. 3. 



Sp. Char. — Body oval. Cephalic-shield subsemicircular, strongly 

 inflated ; limb wide with thickened margin, usually abiuptly 

 deflected ; glabella pyriform or including the circumscribed lobes 

 suboblong, tumid, granulated distinctly ; glabellar furrows in 

 many specimens not visible, but in some the two anterior ones 

 are present, and are short and faint ; axial furrows distinct and 

 continuous anteriorly round the front of the glabella ; circum- 

 scribed lobes separated from the glabella by deeply incised furrows, 

 ovate or obpyriform, prominent, inflated ; fixed cheeks tumid, 

 granulated ; eye lobes in flattened specimens large ; free cheeks 

 moderately large, strongly inflated towards the eye, no granulation 

 observed ; genal angles produced into spines reaching to and 

 including the sixth segment of the thorax, and curving out from 

 the body ; facial sutures anteriorly weakly directed outwards till 

 reaching the thickened edge, then sharply incurved, passing out in 

 a line with the inner side of the eyes, posteriorly sharply curving 

 outwards, cutting the posterior margin of the side lobes at their 

 extremities ; eyes subcrescentic or subreniform, large, facets not 

 observed; neck furrow distinct, continuous across side lobes; neck 

 ring robust, arched, posterior facet strongly granulated; central 

 granule most robust. Thorax consisting of twelve segments ; 

 axis strongly arched, width equal to that of pleurae; posterior 

 facet of each segment carrying a row of granules similar to that 

 of the neck ring, gradually diminishing distally, sixth segment 

 bearing a large dorsal spine extending to the extremity of the 

 pygidium ; pleurae grooved, grooves terminating just short of 

 their extremities, abruptly depressed from fulcra, posterior 

 facets carrying a row of granules, distal ends of pleurae rounded, 



