302 Zoological Society. 



This species is chiefly characterized by the stout double ridge that 

 encircles each whorl near the suture, and by the central ridge that 

 is formed in place of the slit as the shell advances in growth. 



Pleurotoma ctjprea. Pleur. testd acuminato -turrit d, anfractibus 

 superne depressis, fuscescentibus, liris nodulosis, subflexuosis, di- 

 stantibus, longitudinalibus, ornatis ; aperturd brevi, sinu lato. 

 Conch. Icon., Pleurotoma, pi. 17. f. 140. 



The little dark brown flexuous ridges, passing down the whorls of 

 a much lighter brown, have a neat and conspicuous appearance. 



Pleurotoma varicosa. Pleur. testd acuminato-turritd, anfracti- 

 bus superne lavibus, infrci longitudinaliter costatis, costis subirre- 

 gularibus, griseis, interstitiis griseo-cceruleis, transversim striatis, 

 varicibus rudibus lutescentibus grandibus sparsis peculiariter no- 

 tatis ; canali brevissimo, leviter recurvo ; sinu lato, subprofundo. 

 Conch. Icon., Pleurotoma, pi. 17. f. 141. 



Hab. Calapan, island of Mindoro, Philippines (found in coarse 

 sand at the depth of fifteen fathoms) ; Cuming. 

 Var. /3. Testa omninb fusca. 



Hab. Island of Corrigidor, Philippines (found in coarse sand at the 

 depth of six fathoms) ; Cuming. 



This species may be easily recognized by its prominent display of 

 varices. 



Pleurotoma carbonaria. Pleur. testd turritd, carbonarid; an- 

 fractibus prope suturas depressis, lavibus, infra costatis, costis 

 angustis, distantibus, nodulosis ; columelld callositate superne mu- 

 nitd ; canali brevi ; sinu latissimo, prof undo. 

 Conch. Icon., Pleurotoma, pi. 17. f. 145. 



All the specimens I have seen of this dark Melania-like species 

 have the apex either decorticated or broken away, an indication of 

 their living in brackish water. 



Pectunculus spurcus. Pect. testd subquadrato-ovali, gibbd, glauco- 

 fuscd, longitudinaliter costatd, costis numerosis, angustis, subtilis- 

 sime striatis ; umbonibus albicantibus, obliquis. 

 Conch. Icon., Pectunculus, pi. 7. f. 36. 



Hab. Bay of San Carlos (found in coarse sand at the depth of six- 

 teen fathoms) ; Cuming. 



The width of this little species from the umbones to the margin is 

 comparatively shorter than that of any other species. 



Pectunculus pertusus. Pect. testd orbiculari, alba,fusco unda- 

 timpictd; radiatim costatd, costis subtilissime pertusis ; umbonibus 

 centralibus. 

 Conch. Icon., Pectunculus, pi. 7. f. 37. 



Hab. Islands of Mindanao and Luzon, Philippines (found in coarse 

 sand at the depth of ten fathoms) ; Cuming. 



This interesting little species presents a marked peculiarity in the 

 ribs being finely pricked on each side. Two or three specimens only 

 were collected by Mr. Cuming at the above-mentioned islands. 



Pectunculus oculatus. Pect. testd sub-Pectiniformi, radiatim 



