164 



ralibus elevatis et sulcis radiantibus 4-5 insculptis ; intus viri- 

 dans ; ligamentum angustum squamis parvis elongatis sulcatis 

 imbricatum. Long. 15, lat. 10 millim. Hab. Ousima, Bonin 

 and Loo Choo Is. W. S. 



In form like squamulosus and riigulatus, but sculptured differ- 

 ently ; possibly (7. caliginosus Rv. 



C. (Leptochiton) Jacob^us. T. parvula, cinerea, elongata, 

 elliptica vix carinata ; valvis terminalibus permagnis, fornicatis, 

 costis scabris radiantibus ad 10 ornatis ; area centrali cancellata ; 

 areis lateral, couspicuis, bicostatis ; ligamentum angustum, squa- 

 mis minutis elongatis obtectum. Long. 12, lat. 5 millim. Hab. 

 Simoda. W. S. 



The vaulting and ribs of the two large terminal valves make 

 them resemble two small Pectens. 



C. (Leptochiton) concinnus. T. minuta, rubida, elliptica, 

 fornicata, omnino punctata, punctis seriatim dispositis, seriebus 

 radiatim flectantibus ; areis lateralibus haud elevatis, longitud. 

 undulatis ; valva antica crescentica ; v. postica acute umbonata 

 concentrice undulata ; ligamentum angustum, lutescens, pruino- 

 sum. Long. 8, lat. 5 millim. Hab. Hakodadi. W. S. 



In size and form like G. albuSy but sufficiently distinct by its 

 evident lines of punctures. 



C. (Leptochiton) ckaticulatus. T. tenuis, fusco-cinerea, 

 lata, ellij)tica, admodum carinata ; area centrali longitud. clath- 

 rata, clathris elevatis, aeutis ; areis lateral, angustis, elevatis, 

 liris eminentibus asperis divaricantibus 4-8 instructis ; valva an- 

 tica crescentica radiatim lirata ; v. postica vix umbonata radiata ; 

 ligamentum latum, squamis minutis elongatis striatis vestitum, 

 fusco-fasciatum. Long. 30, lat. 20 milHm. Hab. China Seas, 

 probably Simoda. 



The number of ridges on the lateral areas and terminal valves 

 varies much. 



C. (Lepidopleura) lepidus. T. parva, elliptica, tectiformis, 

 flavo-virens olivaceo strigata ; valva antica semicircularis, radia- 

 tim striata ; v. postica crescentica, umbonata, radiata, antice longi- 

 tud. sulcata ; areis lateral, elevatis, sulcis radiantibus ad 6 in- 

 sculptis ; area centrali imbricatim sulcata ; ligamentum angustum 



