338 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. [April 24, 



Obs. Sandberger, Die Yerst. Rhein. Schicht. Nassau, t. 24, figures 

 two or three species of elongated Pleurotomarice resembling our shell 

 in form, viz. P. bilineata, Goldf., P. ( Murchisonia) angulata, Phill., and 

 P. nerincea, Sandb. ; but these shells possess a double line around the 

 middle of the whorls. The original Murchisonia angulata is figured 

 by Prof. Phillips in Pal. Poss. Dev. & Cornw. t. 39. no. 189 ; but we 

 cannot refer our shell to it. I have sought every source, but with- 

 out success, to find any shell agreeing with our Queensland form. 



Loc. Don Eiver. Form. Carboniferous. 



Grifpithides dubius, Ether. PI. XVIII. fig. 7. 



Body elongated, oval, length about twice the width, sides parallel. 

 Axis width of pleurae. Thoracic segments 10 to 12. Pygidium 

 rounded, margins entire ; axis composed of 10 segments, not extending 

 quite to the posterior margin. Cephalic portion much crushed ; gla- 

 bella small and round anteriorly, furrows indistinct. 



Owing to the crustaceous test being removed, we have no means of 

 arriving at the condition of the original ornamentation ; there are, 

 however, indications of tubercles upon the axis of the pygidium. 



06s. It is difficult to say in the badly preserved condition of this 

 specimen whether it belongs to the genus Phillipsia or to Griffi,thides, 

 the mutilation of the head preventing our seeing important characters. 

 I refer it, however, to Grlffithides. This is the only Trilobite I have 

 ever seen from any of the Palaeozoic rocks of Australia younger than 

 Silurian. It much resembles our British foi-ms, especially those of 

 the Carboniferous series ; and as the associated fauna is undoubtedly 

 of this age, we also assign G. dubius to the same horizon. This is 

 very distinct from the other genera of the Proetidae in the Silurian 

 rocks ; the moderate development of the cephalic shield, form of gla- 

 bella, and more elongated body separate it from any known Silurian 

 form. 



Loc. Don River. Form. Carboniferous. 



Mesozoic. 

 Cretaceous. 

 Ctprina expansa, Etheridge. PI. XIX. fig. 1. 



Shell ovato-quadrate, elongated; umbones j)rominent ; umbonal 

 region thick ; ventral margin compressed ; dorsal margin nearly 

 straight ; posterior side slightly truncated ; the line determining 

 the position of the anal adductor and the siphonal sinuses are nearly 

 at right angles to the length of the shell ; these and the pallial sinus 

 are well marked. 



Obs. This sheU appears to have attained to considerable dimen- 

 sions in the Australian Cretaceous seas, being much larger than the 

 Cyprina planata of the Lower Tertiaries of Britain and Prance. 

 In form and habit C. expansa is closely allied to G. planata, pos- 

 sessing also the compressed ventral border, deep lunule, and ex- 

 panded anterior or pedi-lateral margin. Of the many examples we 



