PATELLA-SCUTELLASTRA. 105 



P. PATRIARCHA Pilsbry. PI. 64, fizs. 84, 85 ; pi. 65, fig. 86. 



Shell very large and solid, conical, the apex a little in front of the 

 middle ; rounded oval, nearly as wide as long. Surface dull, coarsely 

 ribbed, 9 or 10 primary ribs radiating from the summit, the secondary 

 ribs numerous, some of them nearly as prominent as the primaries ; 

 radiating striae also are to be seen in some places ; growth-lines fine, 

 inconspicuous. Color dull reddish-ashen. 



Interior pure white, the edge reddish-brown, bordered by a narrow 

 subtranslucent band, sometimes not conspicuous. 



Length 127, breadth 112, alt. 45 mill. 



Length 117, breadth 105, alt. 43 mill. 



Cape Good Hope. 



? P. rustica REEVE, Conch. Icon., f. 8, 1854, not P. rustica Linne 

 (1758), nor P. rustica Menke (1843.) 



This is, next to P. (Ancistromesus) mexicana, the largest limpet 

 I have seen, one of the specimens before me attaining a length of 

 five inches. The interior is pure white, totally lacking the fibrous 

 texture which renders P. ccerulea and its allies iridescent. The 

 shell figured by Reeve as" P. rustica Linn." is probably an immature 

 specimen of this species, having the sculpture sharper. The true 

 rustica of Linue is the small shell known to us as P. lusitanica (q. 

 i 1 .). The rustica of Menke is the same as P. neglecta Gray (q. v.) 



P. TABULARIS Krauss. PI. 16, figs. 9, 10. 



Shell ovate, solid, much depressed, whitish, with radiating reddish 

 lines ; radiately ribbed and striate, the striae and ribs unequal, cari- 

 nated, scaly; larger ribs 12-14 in number. Margin digitately 

 toothed ; vertex obtuse, situated at two-fifths to one-third the length. 



Inside white, having a peripheral border of dull yellow spotted 

 with brown, 2 mill, wide ; space between border and muscle-impres- 

 sion white ; the muscle-scar and central area pale brownish. 



Length 59, breadth 46, alt. 8 mill. 



Table Bay, S. Africa. 



P. tabularis KRAUSS, Die Siidafric. Moll. p. 47, t. 3, f. 8. DKR., 

 Ind. Moll. Guin. Infer, p. 41. P. obtecta KR., I. c. p. 49, t. 3, f. 11. 



Reported by Dunker from Benguela, W. Africa. The strongly 

 angular, star-like form and closely scaly ribs and striae are the 

 prominent characters of this shell. 



