MUSEUM OF COMPARATIVE ZOOLOGY. 193 



I regard these as varieties of one species ; they all possess a small eleva- 

 tion on the columella, with a round button-shaped pillar tooth. They 

 vary in size somewhat, but the dark oblique stride exist, to a greater or 

 less degree, in nearly all examples. The surface in fresh shells is always 

 polished, looking as though oiled. 



From all the examples of P. rufa Less., P. miens Pfr., P. lignaria Pse., 

 and P. affinis Pse., which I have seen, I am inclined to consider them 

 varieties of one species. 



P. gludnosa Pfr., in one quart, was uniform in size and color ; and so 

 was P. virgulata Pse. in the same amount from Raratonga. P. elongata, 

 P. simulans, P. striolata, and P. nucleoid Pse., from the island of Moorea, 

 were present in several pints, and doubtless belong to one species, only 

 varying in size and color, the two last being only depauperated ex- 

 amples of the first. Under the microscope all exhibit the thickly 

 crowded waved spiral striae, and all the varieties show the translucent 

 and banded examples which = P. tceniata Morch. P. elongata Pse., in 

 half a pint, shows the most numerous banded examples. There were 

 present numerous pale yellow elongated specimens, which dealers send 

 out. as P. spadidea Rve. In the parcel of P. simu/ans Pse., the banded 

 examples equalled ten per cent. 



P. nucleoid Pse. Mss. exhibited several very dark opaque examples. 



All the above varieties from Moorea possess to a greater or less degree 

 the dark oblique stria?, the elevation on the columella, the sharp oblique 

 juncture of the labium with the body whorl, and the thickly crowded 

 spiral stria; of the surface of the shell. The latter feature is seen in no 

 other species except P. Mooreana nobis, from the same island. 



P. Hebe Pfr., in half a pint, exhibited nearly all the examples entirely 

 denuded of epidermis, and without a rose apex, the specimens being 

 entirely white and solid. These represent the typical P. J! ! 



P. belld Pse. Mss. = P. rosea var. (according to Mr. Garrett). In 

 almost a pint, the shells possessed a rose apex and were thinner than 

 typical P. I/<be. The epidermis of some of the heavier examples was 

 thin and readily separated from the shell. Many of the more mature 

 specimens were without epidermis. They only differ from P. ffehe in 

 possessing the rose apex, and the lot exhibited the easy grade by which 

 the latter merges into the former. A tew specimens of /'. ;//• bosa Garr. 

 Mss. and P. ventrosa Pse. Mss. were found in the parcel. These vari- 

 eties are more stout and heavy than ordinary examples of /'. 

 They possess a heavy and more adherent epidermis, with little or no 

 color at the apex. All the varieties from /'. //</-< to P. ventroaa present 



vol.. tx. \n. 5, 13 



