366 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



vol. 40. 



the whorls are marked by somewhat retractive, broad, axial ribs, 

 which render the junctions with the sprial cords strongly cuspidate. 

 Of these ribs, about 12 occur on the first to fifth, 14 upon the sixth, 

 18 upon the seventh to tenth, 20 upon the eleventh and twelfth, and 

 22 upon the penultimate whorl. Suture moderately constricted. 

 Periphery of the last whorl marked by a slender sulcus, which is 

 crossed by the continuations of the axial ribs. Base moderately long, 

 concave, ornamented with four strong, rounded, spiral cords, the first 

 of which is immediately below the peripheral sulcus, and the last 

 surrounds the insertion of the columella. These cords grow succes- 

 sively weaker from the periphery to the columella. Aperture irregu- 

 larly subquadrate, decidedly channeled anteriorly; posterior angle 

 obtuse; outer lip rendered sinuous by the external sculpture; colu- 

 mella rather long, curved and twisted, the free edge reflected. 



De Folin's type was taken from pearl oysters which are said to 

 have come from Panama or Negritos Island. (The last may be 

 intended for Negros Island, Philippines.) It has 14 whorls, and meas- 

 ures: Length 6 mm., diameter 1.8 mm. 



EXPLANATION OF PLATES. 



The measurements cited after each species constitute the actual length of the 

 figured specimen. 



Plate 36. 



Fig. 1. 

 2. 

 3. 



4. 

 5. 

 6. 



7. 



Fig. 1. 

 2. 

 3. 

 4. 

 5. 

 6. 

 7. 



Fig. 1. 

 2. 

 3. 

 4. 

 5. 

 6. 

 7. 

 8. 

 9. 



Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 



Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 



Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 

 Cerithiopsis 



subgenus?) excelsa; type; 20.5 mm.; p. 352. 

 Cerithiopsis) oxys; type; 3.5 mm.; p. 332. 

 subgenus?) curtata; type; 2.5 mm.; p. 352. 

 subgenus?) antemunda; type; 5 mm.; p. 359. 

 Cerithiopsis) fatua; type; 6 mm.; p. 331. 

 subgenus?) columna; type; 9.2 mm.; p. 354. 

 subgenus?) gloriosa; type; 8.6 mm.; p. 353. 



Plate 37. 



355. 



subgenus?) infrequens; type; 3.25 mm.; p. 

 Cerithiopsis) sorex; type; 1.6 mm.; p. 333. 

 Cerithiopsis) albonodosa; type; p. 337. 

 Cerithiopsis) abreojosensis; type; 2.3 mm.; p. 338. 

 subgenus?) diomedese; type; 4.3 mm.; p. 359. 

 Cerithiopsis) cerea; type; 2.4 mm.; p. 333. 

 Cerithiopsis) tuberculoides; type; 3.75 mm.; p. 336. 



Plate 38. 



Cerithiopsis) pupiformis; cotype; 1.9 mm.; p. 337. 

 Cerithiopsis) pedroana; cotype; 5.2 mm.; p. 335. 

 subgenus?) fossilis; type; 7.2 mm.; p. 353. 

 subgenus?) paramcea; type; 6.3 mm.; p. 356. 

 Cerithiopsis) pupiformis; cotype; p. 337. 

 subgenus?) bicolor; type; 4 mm.; p. 357. 

 Cerithiopsidella) cosmia; cotype; 9 mm.; p. 348. 

 'subgenus?) magellanica; type; 8.5 mm.; p. 358. 

 Cerithiopsis) carpenteri; cotype; 8.1 mm.; p. 334. 



