TYMPANOTONOS.— Plate I. 



Species 4. (Mus. Cuming.) 



Tympanotonos eadula. Tijin. testa elongato-pyramidali^ 

 irregulariter varicosd ; anfraciibm mimerosis, curtis, 

 s?(2ierne ad suturam motilUferis, turn canaliferis, infra 

 canalem angidalis, et gratwso-costatk, ultimo infra 

 angulato, caaali magno circnlari, labro antice valide 

 prodiicto. 



The boot Tympanotonos. Shell lengtliened, pyrami- 

 dal, irregularly varicose ; whorls numerous, short, 

 beaded above at the sutures, then having a canal, 

 with an angle nest under the canal, and granulated 

 ribs, the last angulated beneath, canal large, circular, 

 outer lip much produced in front. 



LiNN^us, Systema Naturae {Miirex). 



Hah. West Africa, mouths of rivers. 



Eesembling the last species, but without the spire-like 

 prominences. 



Species 5. (Mus. Cuming.) 



Tympanotonos Owenii. Tym. tenia, pyramidali ; an- 

 fractibns numerosis, curtis, angulatis, supertie ad su- 

 turam moniliferis el canaliferis, supra medium angu- 

 latis, ad angulum acute tuberculatis, infra unguium 

 costulis, costis tuberculatis, tuberculis numerosis, vio- 

 niliformibus ; aperturd parvd, labro antice subexpanso, 

 canali parvo. 



Owen's Tympanotonos. Shell pyramidal; whorls nu- 

 merous, short, angular, above at the suture beaded 

 and with a canal, angulated above the middle, with 

 sharp tubercles on the angles, under the angle ribbed, 

 ribs tuberculated, tubercles numerous, bead-like ; 

 aperture small, outer lip slightly expanded in front, 

 canal small. 



Ferussac. 



Hab. West Africa. 



The sculpture in this species is much more coarse than 

 in T. radula, the aperture is smaller, the lip less expanded, 

 and produced in front. This species is, however, rather 

 doubtful. 



Species 6. (Mus. Cuming.) 



Tympanotonos multigranosus. Ti/m. testa elongato- 

 subcylindraced; aiifractibus siiperni subangulatis, costis 

 quatuor parvis moniliferis cinctis; aperturd subquad- 

 ratd, labro vix expauso. 



The many-grained Tympanotonos. Shell elongated, 

 subcylindrical ; whorls above slightly angulated, girt 

 with four small beaded ribs, aperture rather square, 

 outer lip very little produced. 



SowERBY, Thes. Conch. Cerithium, sp. 182, f 302. 



Hab. West Africa. 



The beaded ribs are much smaller, in proportion to the 

 spaces betweeen them, than in the two preceding species. 



