486 CARBONIFEROUS TRILOBITES OF AUSTRAF.IA, 



N.S.W. (Etheridge, Junr., Cat. Austr. Foss., Camb., 1878, p.41). 

 Carboniferous. 



Bkachymetopus dunstani, sp.iiov. 

 (PI. xlix., figs.15, 16: PI. lii., figs.l, 2). 



Complete form unknown. 



Sp. Chars. — Cephalon : length and width 3 mm, and 4 mm., 

 respectively; semielliptic, surface covered with tubercles of vary- 

 ing size, only mildly convex; glabella conical, densely and evenly 

 granulated, very mildly convex, basal furrows well defined and 

 joining the neck-furrow, basal lobes small, greatest width about 

 one-fourth that of the cephalon, length about half that of the 

 cephalon; the surrounding axial furrow relatively deep, cheeks 

 gently convex, bordering the furrow surrounding the glabella; 

 they bear eleven tubercles of uniform size, and follow a course 

 inside of the eyes to the posterior margin: from the front of the 

 eyes there branches from this main bead-like chain of tubercles 

 two other sets (one on each side) of five each, which are arranged 

 along the outer boundary of the eyes; the one or two tubercles 

 in front of, and the one in line with, the back of each eye, appear 

 to be larger than the others of these sets: besides these rows 

 there are a few tubercles bordering the inner edge of the 

 marginal furrow, and the thickened border bears a chain of 

 these small bead-like tubercles of uniform size, and about twenty- 

 five in number, the rest of the surface being finely granulated. 

 The eyes are small, crescentic, close to the glabella and posterior 

 margin; neck-furrow shallow, as are also its lateral extensions: 

 neck-ring fairly robust and granulated, lateral extensions rela- 

 tively strong and narrow; border furrow wide and deep: border 

 strongly tumid and tuberculate; angles, if not spinate, are acute. 



06s. — The above Brachymetopus is the first and only specimen 

 of the genus collected from the Carboniferous rocks of Queens- 

 land. It occurs at Trilobite Ridge, Mt. Morgan, Queensland, 

 associated with other genera of trilobites. In several features 

 it resembles lir. strzeleckii Mc(Joy, the prototype, and agrees with 

 this species and Br. Muccoyi in possessing a well-defined cephalic 

 marginal border, bounded inwardly by a well-defined furrow. 



