BY R. ETIIERIDGE, JUNU., AXD JOHN MITCHELL. 715 



present, long, narrow, very tumid, and granulated, suboqual in 

 length and not fully separated from each other by the basal 

 glabella furrows on the outer sides; false furrows very deep and 

 wide; median glabella furrows very deep, basal pair shallow, wide 

 an 1 not quite passing into the axial furrows; axial furrows dis- 

 tinct and narrow, and passing rather clearly over the genal lol)e 

 ridges. Fixed cheeks of moderate size; genal lobes very tumid^ 

 falling abruptly into the furrows of the lateral extensions and 

 sloping more gradually anteriorly, ocular ridges indistinct, very 

 filamentous; palpebral furrows distinct anteriorly; triangular areas 

 small, lateral extensions short. Neck furrow wide, trough-like, 

 very deep between the false and axial furrows, faint over the 

 genal lobe ridges, thence narrow but distinct. Neck ring robust, 

 thick, very distinctly arched; side lobes or nodules very small, 

 and ridged. Occipital spines acicular and only moderately robust, 

 arcuate. 



Obs. — Thorax, pygidium, and free cheeks are unknown. It 

 approaches nearer to C. Jackii than any other known Australian 

 species, and from this it is readily separable by the much greater 

 tumidity of the cephalon and its distinctive granulation; the 

 longer central glabella lobe and its greater convexity; the longer, 

 narrower, and moz'e tumid lateral glabella lobes; the shorter 

 lateral extensions of the fixed cheeks; by the more ridge-like pro- 

 minent frontal glabella expansions and its prominent tubercle; 

 and lastly by the veiy small lateral lobes of the occipital ring. 

 The proportionate width between the eyes and length of the 

 glabella is also difterent in the two species. From C. longisjyiua 

 it is separated by the same characters. 



Lor. and Horizon — Bowning Village, Co. Harden, Middle 

 Trilobite Bed — Bowning Series ( = Hume Beds, Jenkins, and Yass 

 Beds, David)— ^ Wenlock. Co//.— Mitchell. 



Ceratocephala longispina, Mitchell, sp. 

 (PL Liii., fig. 10; PL liv., figs. 1-5.) 



Acidaspis near A. inira, Ratte (non Barr.), Proc. Linn. Soc. N.S. 

 Wales, i. (2), Pt. iv. p. 1069, t. 15, f. 13, 14. - 



