178 



minoribua plus minusve muriculatis interpositis ; v. altera costis fre- 

 quentioribus minoribus squamigeris, costulis muriculatis interpositis ; 

 auriculis (nisi area ad sinum tendente) radiis numerosis spinulosis 

 munitis ; cavositas valvae integrae rubricata ; v. altera? pallidior, fere 

 alba. Long. 3.5 ; alt. 3.75; lat. 1.5 poll. Inhabits Hakodadi Bay, in 

 shelly mud, 10 lath. W. S. 



Resembles generally P. senatorius, but is more elongated, the small 

 ear longer, and the ribs much less regularly disposed. It is still more 

 like P. caurinus G. in which the ribs are angular and more regularly 

 disposed. In old and heavy specimens the scales are worn off; and 

 in some young specimens, too, they are inconspicuous. 



Ostrka iuvulakis. T. discoidea, subcircularis, tenuis; valva 

 inferior crassior, purpurascens, costis radiantibus remotis, interrupts, 

 subtubulosis munita ; v. superior simplex, rivulis ramosissimis purpur- 

 ascentibus venosa : cavositas minime profunda, ovata, alba cinereo 

 late marginata ; cardine debili. Diam. GO; lat. 10 millim. Inhabits 

 the China Seas, as indicated by shells adhering to it. 



The rays of little tubes below, and the veins above, are unusually 

 clear, distinctive characters. 



Plicatula simplex. T. parva, solida, cinerea vel rubida, flabelli- 

 formis, symmetrica, quadrantem haud a3quans ; marginibus rectis, 

 planulatis ; costis praecipuis 6 et costulis numerosis lateralibus, etiam 

 laminis concentricis numerosis munita. Long. 15 ; lat. 8 millim. 

 Common at Kagosima Bay and Simoda, 5-20 fath. W. S. 



Placixanomia umbonata. T. discoidea, talcosa, fragilis, admo- 

 dum levigata, straminea : valva superior obsolete radiata, et umbonem 

 submarginalem monstrans ; fossa cardinali minime profunda : v. in- 

 ferioris perforatione acute-ovato ; clavicula vix dilatata, quasi costa 

 secundum marginem perforationis prolongate. Diam. 25; lat. 4 mil- 

 lim. Inhabits Kagosima Bay. W. S. 



It most resembles P. claviculata from Mazatlan. 



The preceding descriptions were published in the Proceedings of the Boston 



Society of Natural History, under the following dates, beginning with — 



PagelOl. Succinea laata ------- Vol VI. 422. Feb. 1859. 



• 105. " lyrata ------- " VII. 40. June, 1859. 



" 110. Paxillua tantillus ------ " " 138. Oct. 1859. 



" ll">. Patellagrata --- " " 161. Dec. 1859. 



" 120. Terebratula transversa- - - - - " " 323. Sept. 1860. 



" 183. Drilliaeborea- ------- " " 337. Oct. 1860. 



" 137. Mangelia semiassa ------ " " 382. Dec. 1860. 



" 140. Turritella gracillima ----- " " 386. Jan. 1861. 



" 145 Eissoina vfflica - - " " 401. Feb. 1861. 



" 158. Tectarius luteus - ------ " VIII. 14. Mar. 1861. 



" 171. Mysia obliqua ------- " " 33. Ap'l, 1861. 



