Mr Ether idgc on Fossils from Bo wen Elver Coalfield. 307 



specimens are identical, and in the face of this I do not think 

 the above difference is of sufficient importance to base a 

 separation on. 



Loc. and Horizon. — Tate Eiver, N. Queensland, from beds 

 of Cretaceous a^e. 



Collector.— 'R. L. Jack, Esq. 



Appendix. 



I take this opportunity of describing a Strojjlialosia in the 

 collection of the British Museum, and in that of Mr T. David- 

 son from New South Wales and Tasmania respectively. I 

 first observed this form in a collection of fossils made by 

 the late Professor J. B. Jukes, F.R.S., in Australia, and now 

 in the British Museum. I provisionally apply to them the 

 name of Strojplmlosia Jukesii, as they may be only a variety of 

 the species just described, S. Gera7'di{T)^ but as explained 

 further on, the want of intermediate forms has induced me 

 to consider them as at present distinct. 



Strophalosia Jukesii, sp. nov. (?). — PI. XIII., figs. 39-43. 



Sp. Clrnr. — Shell subquadrate, sometimes contorted, oval, 

 or approaching the deltoid, almost plano-convex when the 

 valves are in apposition. Ventral valve very convex and 

 gibbous, most so about half-way between the umbo and the 

 front of the valve, with a shallow but distinct mesial sinus, 

 lateral angles rounded ; front margin rounded, and sometimes 

 a little indented, or occasionally a constriction, or slit, occurs 

 either in the centre of the front, or to one side of it. Hinge 

 line much shorter than the width of shell ; umbo depressed, 

 projecting a little over the hinge line, but not at all promi- 

 nent. Area elongately-triangular, a little concave, longitu- 

 dinally striated ; fissure narrow and badly defined, covered 

 by a small convex deltidium. Dorsal valve quadrate to 

 deltoid, flat or very slightly concave, the concavity having 

 no comparison to the convexity of the ventral valve ; area 

 small and triangular. Internal characters strongly marked ; 

 cardinal boss prominent, projecting at an angle of about 119° 



