JOURNAL ROYAL SOCIETY, N.S.W., 1888. putois. Part u. 



Figs. 20 and 21. Exterior of right and left valve Trigonia lamarckii. 



Fig. 22. Interior of valve of Trigonia lamarckii. 



Fig. 23. Interior of valve of Trigonia margaritacea. 



Fig. 24. Exterior of valve of Trigonia margaritacea. 



