PLAXIPHORA. 331 



" Frembleya, gen. nov. Testa ovalis, convexa. Valvse transversse, 

 latse, carinatee ; apex posterioris valvse terminalis, producta, fissa. 

 Limbus angustus, postice fissus, setis cornels dense obsitus. The 

 covering of the mantle, the form of the visible portions of the valves, 

 and the peculiarity of the terminal valve, render this species distinct 

 from any form of Chitonidse yet described. It has the appearance 

 of a Lorica with the mantle covered with long bristles instead of 

 imbricate scales." 



There seems to be no reasonable objection to the correction of the 

 etymology of Frembly's name, which in H. Adams' article was 

 incorrectly spelled through inadvertence or typographical error. 



P. EGREGIA H. Adams. PI. 65, figs. 80, 81, 82. 



Shell ovate, a little narrower in front, green-brown, paler at the 

 sides. Anterior valve radially ribbed, the ribs pustulose, interstices 

 obliquely lirate ; posterior valve and median valves subcarinate, the 

 dorsal areas densely longitudinally lirate; lateral areas radially rib- 

 bed, the ribs pustulose. Girdle moderate, furnished with short, 

 corneous spicules. (H. Ad.) 



Length 15, breadth 9 mill. 



"Habitat unknown" (Ad.); Newcastle, Australia (Dieffenbach, 

 teste Cpr.) 



Frembleya egregia H. AD., P. Z. S. 1866, p. 445, t. 38, f. 9. 

 Streptochiton tortuosus CPR., MS., olim. 



Of this species I have seen a single mutilated specimen, no. 36,638 

 of the Smithsonian Institution register. It is yellowish along the 

 middle and at the side margins of the valves, pale green on the side- 

 slopes. The species differs from P. ovata in being widest behind the 

 middle. Carpenter describes the type as follows : Shell olivaceous, 

 maculated with more or less intense ; ovate, broad, elevated ; dorsal 

 ridge rather acute, much elevated, the side-slopes straight. Valves 

 strongly beaked, each one eroded in front from the attrition of the 

 next valve forward. The central areas have about 16 lirse on each 

 side, about equalling the interspaces in width. Lateral areas elevated, 

 bicostate, the ribs strongly granose, granules larger at the sutures, 

 intermediate space obliquely costate or v-costate. Anterior 

 valve having 10 radiating ribs, the interstices sculptured with 

 v-shaped sulci, the v'-s meeting over the ribs and rendering them 

 somewhat nodulous. Posterior valve with posterior elevated mucro 

 and a single posterior rib on each side ; posterior area very narrow 



