60 CHONEPLAX. 



size. The slits of the insertion-plates are less obsolete than in 

 Cryptoplax. 



C. LATUS Guilding. PI. 8, fig. 15. 



Elongated, narrow, vermiform ; the valves strongly imbricating, 

 eroded, generally dirty white with a dull brown median band or 

 area, the unworn side margins brown. Interior of valves bluish or 

 gray, generally black in the cavity. 



The intermediate valves are squarish, very blunt behind, and 

 when unworn are minutely granulated at the sides, with an indis- 

 tinctly defined dorsal smooth band. Posterior valve smaller, with 

 posterior mucro. 



Interior dark colored, the median valves having the sinus very 

 narrow, deep and square. Anterior valve having 3 slits, other 

 valves none. Posterior valve having a long sharp insertion plate, 

 directed forward ; much hollowed out. 



Girdle wide, brownish, covered with minute spicules, having a 

 fringe of longer white spinelets around the border of the ventral sur- 

 face, and provided with 9 small tufts of brown spinelets on each side. 



Length about 25 mill. 



St. Thomas and Ouadaloupe (R. Swift ! in Coll. Phila. Acad.) ; 

 St. Vincent (Guilding !) ; Portorico (Blauner !). 



Chitonellus latus GUILDING, Zool. Journ. v, p. 28 (1829). Chiton 

 strigatus Sown., Charlesworth's Mag. of Nat. Hist. 1840, p. 289 ; 

 Conch. Illustr., f. 63. Chitonellus strigatus REEVE, Conch. Syst. ii, 

 t. 135, f. 6. Phalcellopleura (Acantkochites) strigata SHUTTLW., 

 Bern. Mittheil. 1853, p. 80. Chitonellus Icevis REEVE, Conch. Icon, 

 f. 1. Not of Lamarck. Choneplax serpens CPR. MS., olim. Chone- 

 plax strigatus CPR. MS. 



The name latus is not preoccupied in the Cryptoplacidce and being 

 the earliest published it must be accepted. The valves of this 

 species are greatly eroded in all the specimens I have seen. 



C. HASTATUS Sowerby. PL 8, figs. 16-22. 



Shell small, granulated ; valves reclining, acute, the first five very 

 narrow, the latter three wider ; the last having a pointed terminal 

 apex ; margin thick, rude, having minute red tufts at the valves. 



Length 9, breadth 3 mill. (Sowb.) 



Habitat unknown. 



Chiton hastatus Sows., Charlesworth's Mag. of Nat. Hist. 1840, 

 p. 290, Suppl. pi. 16, f. 4; Conch. Illustr. f. 127. REEVE, Conch. 

 Icon., f. 166. Choneplax hastatus CPR., MS. 



