98 PATELLA-SCUTELLASTRA. 



In the form called chitonoides Rv. (pi. 26, figs. 28, 29) the ribs are 

 somewhat more numerous, and the entire surface is purple-black. 



I am unable to find differential characters in the P. moreli of 

 Deshayes. I have copied the original figure on pi. 58, fig. 45, re- 

 presenting an immature specimen. The same is true of P. levata 

 Dh. (pi. 59, fig. 46). 



This species seems to be more than usually encrusted with 

 calcareous growths, algse, etc. The specimens before me are from 

 Mauritius, collected by Robillard. 



P. EXUSTA Reeve. PI. 24, figs. 9, 10. 



Shell ovate, a little attenuated in front, flatly convex, rather 

 spread ; apex inclined anteriorly ; radiately ribbed, ribs with the 

 surface rude, irregularly, obscurely prickly-scaled, interstices 

 obsoletely latticed, with rather distant concentric ridges; burnt- 

 black, red-tinged, interior marble-white ; edge remotely denticulated, 

 purple-black. 



An extremely characteristic species, marble-white within, reddish- 

 burnt black without, but of singular rude irregular, obsoletely 

 latticed sculpture. (JRve.) 



Habitat unknown. 



P. exusta RVE., Conch. Icon., f. 35, Oct., 1854. 



This may prove to be the same as P. pica Reeve. If so the name 

 exusta will take precedence. 



P. FUNEBRIS Reeve. PL 60, figs. 59, 60, 61. 



Shell ovate, slightly attenuated in front, elevately convex ; smooth, 

 rayed with tubercled ribs, tubercles swollen, sometimes rather 

 distant. Dull black, rusty-white at the apex. Interior opaque 

 white, sometimes rust-tinged. (Rve.) 



Habitat unknown. 



P.funebris RVE., Conch. Icon., f. 54. 'Dec., 1854. 



P. STELL^FORMIS Reeve. PI. 17, figs. 25, 26, 27 ; pi. 61, figs. 62-65. 

 Shell solid, low-conic, angularly oval, the apex central. Surface 

 vary irregularly and roughly sculptured with carinated radiating 

 ribs and riblets, 8 or 9 being more prominent in the typical form of 

 the species. The ribs are rude, irregular, often somewhat scaly. 

 White, sometimes marked in the interstices with black or rusty- 

 black. 



