OF MOLLUSCA. 29 



Fasciolaria granosa is found among stones in muddy places near 

 low water mark. 



2. Leucozonia. 



Shell ovate, fusiform, swollen like Latirus, but with a tooth at 

 the end of an external groove in front of the outer lip. Operculum 

 ovate, acute, rather curved. — Adams, Gen. Moll. t. 16. f. 6 a. 



1. L. smaragdula, t. 35. f. 21 ; Adams, Gen. Moll. t. 16. f. 6. 



Central tooth of Leucozonia brasiliana narrow, three-toothed ; 

 lateral broad, many-toothed. — Morch. 



3. Latirus. 



Shell ovate, fusiform, swollen ; spire moderate ; whorls smooth or 

 rather waved ; mouth ovate ; outer lip with a distinct tooth in front, 

 grooved within ; inner lip smooth ; pillar with a few small transverse 

 folds in front. Operculum ovate, acute. 



1. L. rusticus, t. 8. f. 6. 



2. L. lineatus, t. 8. f. 8. 



3. L. polygonus, t. 8. f. 7. 



4. L. nussatellus, t. 8. f. 1 ; Adams, Gen. Moll. t. 16. f. 5. 



Lingual membrane of Latirus rusticus with three series of teeth ; 

 central narrow, recurved and three-toothed ; lateral teeth very broad, 

 linear, many-toothed on the edge, not versatile. 



Central tooth of Latirus filamentosus narrow, three-toothed ; lateral 

 broad, many-toothed. — Morch. 



b. Mitrana. Operculum none. Canal of shell short. Central tooth 

 broad, denticulated. 



4. Mitra. 



Shell fusiform ; spire conical ; whorls compressed ; mouth ovate, 

 linear ; outer lip smooth within ; pillar with five plaits ; mantle en- 

 closed ; siphon without any auricles at the base. Foot small, folded 

 longitudinally when contracted. Operculum none. 



1. M. episcopalis, t. 28. f . 6 ; t. 106. f. 4. Central tooth broad. 



2. M. adusta, t. 28. f. 3, 4. Central teeth narrow, simple, hooked. 



3. M. maura, t. 106. f. 5. 



4. M. retusa, t. 28. f. 5. 



5. M. nigra, t. 28. f. 1. 



Proboscis of Mitra cucumerina thick. Teeth 1*1*1; central 

 moderate, transverse, front edge arched with seven rather distant, 

 conical, transparent teeth ; lateral elongate, transverse, with nume- 

 rous, rather distant, conical, transparent teeth on the front edge. 



Tongue of Mitra adusta with teeth, 1*1*1; central with a strong 

 hook and a small denticle on each side ; lateral transverse, elongate, 

 linear, with many teeth on the front edge, largest near the inner 

 edge, and smaller near the outer. 



