BY n. ETHEKIDCK, JUNR., AND JOHN MlTCHEr,L. 50 1 



Bkonteus bowningensis, sp.nov. 

 (Plate xxvi , fig. 6.) 



Sp. Chars. —Fyyidinm : exact sliape unknown; type specimen 

 smooth, but there is faint evidence of sparse gtanulation, the 

 characteristic striation of t}ie Bronteidte distinct (especially on 

 the axis and central rib), Hat, hardly at all tumid: articulating 

 Ijorder straight, and apparently forming the line of greatest 

 width: axis truncate-pyramidal, slightly tumid and distinctly 

 trilobed, less wide than the pleural lobes, articulating ring nar- 

 row; axial grooves shallow, distinct and continuous along each 

 side of the central rib: pleurae flat, wide, separated by relatively 

 narrow sulci, four on each side of central one, ridged near their 

 origin, central one wide, Hat, and depressed 



Obs. — This pygidium, though very imperfect, exhibits features 

 so very different from all other Australian Jirontei known to us, 

 that it is needless to discuss them; and it stands apart fronj all 

 foreign species with which we have been able to compare it. For 

 this reason, we venture to give it speciHc rank. 



Loc. and Hor. — Parish Bovvning, County Harden: Upper Tri- 

 lobite beds, Bowning Series. Upper Silurian. 



Bronteus molongensls, sp.nov. 

 (Plate xxvi., tig.8.) 



C^eplialon and thorax unknown. 



Sp. Chars. — /*y_r/ic?i?<m sub-semielliptic, width 36mm., length 29 

 mm., surface smooth, bearing numerous very fine, subcoucentric, 

 anastomosing lines; greatest width at one-third of total length 

 from the articulating border, which is straight, 28 mm. long, its 

 outer angles rounded; axis(rudimentary) widely triangular, rather 

 strongly inflated, trilobed, central lobe strongly arched; axial 

 furrow shallow, and practically interrupted by the cential rib, 

 which bifurcates at a point nearly two-thirds of the length from 

 the articulating border; this central ridge or extension of the axis 

 is distinctly arched and slightly more prominent between the 

 rudimentary axis and point of bifurcation, than are the pleural 

 ribs; the pleurae are divided into segments or ribs, these are moder- 

 ately rounded, wide and separated by well-defined furrows nar- 



