120 Proceedings of the Royal Society of Victoria. 



the Cambrian of Curramulka, South Australia, under the name 

 of H. communis, Billings, is not far removed from our specimen 

 in general appearance, but the strise are finer and the shell is 

 proportionately shorter.'^ 



Locality and Horizon. — Collected by the Geological Survey of 

 Victoria, W.L.S.2 [197], Parish of Coole Barghurk. Lower 

 Ordovician. 



EXPLANATION OF PLATES XVL, XVIL AND XVIIL 

 Plate XVI. 



Pig. 1. — Bythotrephis ienui<;, J. Hall. Natural size. [246]. 



Pig. 2. — Pleurodictytim megastonmm, Dun. A cast of the 

 corallum of a very large specimen. Natural size. 

 [340]. 



Pig. 3. — P. viegastoimiin. Base of a well-preserved specimen, 

 showing the epithecal surface, and an impression 

 of a crinoid stem-fragment to which the coral was 

 originally attached. Natural size. [341]. 



Pig. 4. — P. megastomum. Taken from a wax squeeze, showing 

 the under surface of a tabula, with radial ridges 

 and tubercles. Natural size. [340]. 



Pig. 5. — P. megastomum. Two radial ridges of the above 

 more highly magnified, to show the quasi-linear 

 arrangement of the tubercles. x 3. [340]. 



Fig. 6. — Beyrichia wooriyallockensis^ sp. nov. Right valve ; 

 taken from a wax squeeze. X 12. [446]. 



Fig. 7. — Beyrichia tnaccoyiana, Jones, var. australice, nov. 

 Left valve, x 10. [441]. 



Pig. 8. — Beyrichia klxdeni, M'Coy, var. grafiuiata, Jones. 

 Kight valve; a specimen showing the hypertrophied 

 anterior lobe. Prom a wax squeeze, x 7. [440]. 



Pig. 9. — Beyrichia kihnoriensis, sp. nov. Left A^alve. x 11. 

 [445]. 



Fig. 10. — Beyrichia iigatura, sp. nov. Right valve. x 15. 

 [444]. 



2 Trans. R. Soc. S. Axiatralia, vol. xv. (1891-2), p. 186, pi. ii., fig. 2. 



