BY JOHN MITCHELL. 465 



was submitted by Mr. Dunstan, Chief Government Geologist, 

 Department of Mines, Brisbane, to Mr. Etheridge, who described 

 it briefly,* placing it with P. yrandis. This same specimen has 

 been used for the above description. It will be seen that, in 

 the description of the parts of the fossil, we are not in agreement, 

 our dimensional estimates, strangely, differing rathei- widely. 

 The dimensions arrived at by myself are :~ 

 Cephalic shield, length 30 mm. 

 Length of thorax, 20 mm. 

 Greatest width, 45 mm. 

 Length of tail, 34 mm. 

 Greatest width, 44 mm. 



Total length of trilobite, 84 mm., or nearly 3i inches, A giant, cer- 

 tainly, among Carboniferous trilobites. 

 The reasons for separating the pygidium from Swain's Selec- 

 tion, near Carroll, N.S.W., from the Queensland forms, are fully 

 entered into under the re-description of the New South Wales 

 form, under the name of PJiillipsia robusta mihi. 



The distinguishing features of the present species are — 1. Its 

 great size. 2. The largeness of the free cheeks, their ornamenta- 

 tion, and great width of their borders. 3. The relatively narrow 

 pygidial axis. 4. The mild tuberculation of the bases of the 

 thoracic and pygidial axial rings. 5. The slight tuberculation 

 of the pleural segment at the inner margin of the border, and 

 their claw-like shape, as they cross the border. 6. The plainly 

 visible sutures along the articulating ridges of the pleural seg- 

 ments, and the fine and close granulation of these ridges. 7. The 

 strongly ridged and furrowed somites of the pygidium. 



As Mr. Etheridge has pointed out, it is uncertain still whether 

 this trilobite belongs to the genus Phillipsia or to Griffithides, 

 but the evidence available indicates the former. 



Loc. and Uor. — Crow's Nest, near Mt. Morgan, Queensland. 

 Carboniferous. 



Phillipsia woodwardi Eth. fil. 

 Phillipsia woodwardi Eth. fil., Geol. and Pal, Queensland and 

 New Guinea, 1892, p.215, PI, vii., figs.ll, 13; PI. viii., fig.6; and 

 PI. xliv., figs.5-6. 



* Geol. Survey Queensland, Publication No.260, 1917, pp. 11-12, PI. iii., 

 fig. 3. 



