524 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.51. 



9. Turritella haUnsis Ball, from a cast; length of entire figure, 57 mm.; p. 517. 



10. Xenophora conchyliophora Born, internal cast; maximum diameter, 42 mm.; 



p. 518. 



11. Bittium silicium Ball; length, 20 mm.; p. 510. 



12. Cerithium insulatum Ball, from a cast; length, 19 mm.; p. 516. 



Plate 87. 



Fig. 1. Cerithium vaginatum Ball, length of defective shell, 22 mm.; p. 515. 



2. The same, fragment showing detail of spire; length, 17 mm.; p. 515. 



3. The same, cast of last whorl showing intensified sculpture; height of whorl, 



11 mm.; p. 515. 



4. Cerithium silicifluvium Ball, cast of apex, length, 19 mm.; p. 511. 



5. The same, cast of decollate specimen; length, 45 mm.; p. 511. 



6. Cerithium corullicolum Ball, length of entire figure, 47 mm.; p. 514. 



7. Cerithium eutextile Ball, length of shell, 39 mm.; p. 515. 



8. Cerithium vaughani Ball, cast; height of shell, 32 mm.; p. 513. 



9. Cerithium lialense Ball, length of entire figure, 60 mm.; p. 512. 



10. The same, cast showing sculpture of lower whorls; length of shell, 26 mm.; 



p. 512. 



11. Cerithium cookei Ball, height of shell, 41 mm. ; upper part of apex obscured; 



p. 513. 



12. Cerithium mascotianum Ball, length of entire cast, 53 mm.; p. 512. 



Plate 88. 



Fig. 1. Marginella silidfluvia Ball, length, 8.5 mm.; p. 504. 



2. Marginella halensis Ball, length, 2.75 mm.; p. 504. 



3. Epitonium ? dubiosum Ball, diameter, 1.5 mm.; p. 506. 



4. Liotia (Arene) halensis Ball, diameter, 3 mm.; p. 521. 



5. Margarites corallicus Ball, l)ack view, diameter, 3 mm.; p. 520. 



6. The same, showing spire, diameter, 3 mm.; p. 520. 



7. Teinostoma sublimata Ball, base; diameter, 4 mm.; p. 520. 



8. The same, front view; diameter, 4 mm.; p. 520. 



9. Orthaulax inornatus Gabb, fragment showing spii-e; p. 509. 



10. Bursa victrix Ball, cast from mold, length of entire figure, 48 mm.; p. 507. 



11. Amauropsis ocalana Ball, internal cast; height, 40 mm.; p. 519. 



12. Miltha hillsboroinsis Heilprin, right valve; altitude, 48 mm.; p. 498. 



13. Fusinua nexilis Ball, cast; height, 17.5 mm.; p. 505. 



