EXPLANATION OE PLATIil I. 
Fig. 1. 
Fig. 4. 
Fig. .5. 
Fig, (!. 
Fig. 7. 
Fig. 9. 
Fig. 10. 
Fig. 11. 
Fig. 12. 
Fig. 13. 
Fig. 14. 
Fig. 15. 
Fig. IG. 
Fig. 17. 
Fig. 18. 
Fig. 19. 
Fig. 20. 
Fig. 21. 
Fig. 22. 
Fig. 23. 
Page 
EsTiiEarA CocL.wi, Cu.r. ... ... ... ... G 
Lateral view of the normal form. 
similar sjK;cimeii, obliejuely criisliecl, and witli the umbo produced. 
.Vn individual pressed from al)Ove, with the umbo rather dis[)lacud. 
Two valves crushed togcthei-, illustrating the manner in which the Eatkervr occui- 
(Surface ornament, highly enlarged. 
Figs. I are from drawings of specimens from tlie Dent’s th'cek Bore, and supplied 
l)y Dr. .J . ( '. Co.v ; magnified al)out lO. 
Estiieuia (1), up. 
Lateral view of an indistinct valve, froin 1,48.3 ft., in the Dent’s Creek Lore x 5 
^\.n obli([uely pres.sed and distorted valve from a depth of 1,915—1,955 ft. in the 
same bore... ... ... ... ••• ••• x 4 
Another example which has assumed a triangular form 1,932 ft. in the same 
bore ... ... ... ... ... ... ... ... ... X 5 
Portion of an indistinct valve, distorted into a triangular or deltoid outline, from 
2,000 ft. in the Dent’s Creek Boro ... ... ... ... ... x 5 
Fragment of a valve from a depth of 1,9G1 ft. in the Narrabeen Bore ... x 5 
U.xio Dunstani, Eth,., jnr. 
Lateral view of a small specimen showing the long hinge and muscular scars x 2 
Dorsal view of the same S{)Ocimen, exhibiting the relative thickness of the 
internal cast ... ... ... ... ... ... ... ... x 2 
A much larger example, with portions of tlie shell remaining ... ... x I 
Dor.sal view of Fig. 13 ... ... ... ... ... ... ... x 4 
A larger anil somewhat more robust individual, with portions of the shell still 
retained ... ... ... ... ... ... ... ... ... x4- 
Dorsal view of the same ... ... ... ... ... ... ... x i 
A specimen in which the anterior adductor imjiression is visible, and the umbonal 
scars faintly indicated ... ... ... ... ... ... ... x2 
Dorsal view of the same ... ... ... ... ... ... ... x 2 
A small shell in which the extreme attenuation of the shell towards the posterior 
end is shown ... ... ... ... ... ... ... ... x 
11 
Figs. 1L19 ai-e from Bowral Specimens. 
Unionella Carnei, Eth., jnr. ... ... ... ... 14 
Side view of an im[)erfect specimen crushed from above ; Bowral ... x 2 
Unionella Bowralensis, Eth., jnr... .. ... ... 13 
Portion of two valves obliquely pressed from above ... ... ... x3 
Doivsal view of another individual, showing the thickness of the valves, and the 
ligament ... ... ... ... ... ... ... ... ... x 3 
A mass of ironstone with valves of Unionella Boioralensis, and Unio Dunstani 
scattered through it. 
Figs, are from Bowral specimens. 
11a 1-24—88 
