462 CARBONIFEROUS TKILOBITES OF AUSTRALIA, 



wider than the pleurse if measured horizontally. Axial grooves 

 linear. Side-lobes between the axial grooves and fulcra almost 

 horizontal, thence nearly perpendicular ; somites apparentl}^ 

 faceted, medial grooves very shallow, ridges feeble. 



Pygidiuni semielliptic, length 6 mm., width 7 mm., smooth. 

 Axis very prominent, made up of twelve if not thirteen annula- 

 tions, but not more than ten usually visible owing to the slender- 

 ness of the posterior ones. Posteriorly it contracts gradualh', 

 and ends a little short of the border with about half the anterior 

 width; in some specimens, the rings centrally show emargination 

 and other indications of having borne fine tubercles. Axial 

 grooves faint Side-lobes convex, consisting of eight pairs of 

 segments whose valleys and ridges are inconspicuous, and the 

 ends, as they approach the border, bifurcate, or, more correctl}^, 

 the sutures widen out and make the segments appear to have 

 free ends; the individual segments have little or no backward 

 curve, and the last two pairs are indicated merely by a very faint 

 ridge and tubercle; border continuous and relatively wide, con- 

 centrically and finely striated underneath, only slightly thickened 

 and separated from the segments by a fine suture. 



06s. — This beautiful trilobite was originally described by K. 

 Etheridge, Junr., and with it was joined Griffithides dubiiis Ether- 

 idge, Senr., for reasons not explained. All the evidence avail- 

 able leads me to conclude that the two are not specifically the 

 same, and to regret that this very typical Phillipsia above-de- 

 scribed should have been in any way linked with Griffithides 

 diihius Eth. Senr. An examination of the figure given of this 

 latter trilobite reveals that the glabella has three continuous 

 lateral furrows, and a shape altogether unlike the former species; 

 and, further, the latter is represented as having thirteen or four- 

 teen axial rings, and an equal number of pleural segments in its 

 pygidium; while the former has only twelve and eight, respect- 

 ively, in the similar parts of the pygidium. These differences 

 place the two apart. 



As may be observed (antea, under the description of P. 

 elonyata mihi), I have had to disagree with Mr. Etheridge in 

 determining that, and the above form to be specifically the same, 

 for which divergence of opinion reasons are given. 



