< n< >N i:ri,.\ \ . 



inarulis ra-nili-is niarniorat mn ; vulva antica i-lliptirji ruiroaa; 

 valvarum intrnncdianiin area << utralis aiiL'iiMa, rotundata, .p 

 inihricatis smipta : arris latrrnlilnis, sulris divan<-;itis, ragOtb, WTO- 

 atis. Li.iramt'iitM martinis limhriato. Long. 0,040; lat. <. 



ln>l>r., Bull. Soc. Philom. 1881-82, p. 196.) 

 A ' - , A- ?r ( \dnlnnia (MM. Beaudoin andHeurtel). Not common. 

 Paris Mus. 



Cryptoplax In nHdi Rochebrtine. Corpus ovatuin, villosuin, antice 

 posticeque rotundatum ; luteo roseum fasciis 2 latis, rubris cinctum ; 

 valva antica rotundata, Isevis; valvis centralibus viridescentibus, 

 ininiitissiniis, areis medianis licvibus, lateralibus longitudinaliter 

 striatis, striis denticulatis. Ligamento marginis, setis longis vestito. 

 Long. 0,028; lat. 0,009. (Rochebr., Bull. Soc. Philom. 1881-'82, 

 p. 196.) 



New Caledonia (M. Heurtel) ; Rare ; Mus. Paris. 



Cryptoplax unciniferus Rochebrune. Corpus elongatum, antice 

 attenuatum, postice latum, glaberrimum, luteofuscum ; valvis 

 coeruleis, antice subquadrata, postice intense umbonate, umbone 

 acuto ; ceteris angustis, unciniferis ; area centrales minute punctata ; 

 lateralibus circulariter sulcatis sulcis imbricatis, nodosis. Long. 

 0,068; lat. 0,010. (Rochebr.-). Bull. Soc. Philom. 1881-'82, 

 p. 197. 



Xew Caledonia (Museum of the Colonies ; M. Heurtel). Common. 

 Paris Mus. 



Genus CHONEPLAX Carpenter, 1882. 



Choneplax CPR. in Dall, Proc. U. S. Nat. Mus. 1881, no. 49, 

 p. 285, 288 (Jan. 20, 1882). Type C. strigatm So\\b. Chitoniscus 

 CPR. (part) I. c., no. 49a, p. 285, 288. Types 4< Chiton<-Un. -trlntns 

 and strigatus Sowerby, Conch. 111., figs. 62 and 63." 



Much elongated, somewhat vermiform. Valves subequal in 

 and all strongly overlapping, the mucro of the tail valve projecting 

 far backward. Insertion and sutural plates all strongly drawn for- 

 ward, the anterior valve with 3-5 shallow slits, the other valves hav- 

 ing one slit on each side or none. Girdle minutely setose, and hav- 

 ing sutural tufts, sometimes obsolete. Gills posterior. 



Distribution, West Indies. 



This genus, whilst closely allied to Orypt"jit'ur, differs in the strong 

 imbrication of all the valves, and their much greater com par; 



