HELIX-POLYDONTES. 79 



Section III. POLYDONTES Montfort, 1810. 

 Polydontes MONTF., Conch. Syst. ii, p. 154, and of authors. 



This section seems to be much more closely allied to Thelidomus 

 und especially Parthena than to Caracolus, and should have been 

 placed in the preceding group. I now place it here because it was 

 omitted in the synopsis of sections on p. 56. The animal has not 

 been observed. 



Key to species of Polydontes. 



Peristome toothed within, imperator. 

 Peristome not toothed, 



Periphery strongly carinated, apollo. 



Periphery very obtusely carinated or rounded, sobrina. 



H. IMPERATOR Montfort. PI. 9, figs. 80-83, 87. 



Imperforate or narrowly unibilicate, depressed, heavy, thick, 

 solid, opaque, nearly lusterless, yellow, densely obliquely streaked 

 with light chestnut, and with very numerous but inconspicuous 

 spiral lines of the same above ; surface with rather coarse irregular 

 wrinkles of increment, and under a lens seen to be covered with an 

 excessively minute decussated sculpture; spire low-conical; whorls 

 5 ; body-whorl depressed, carinated, a trifle descending anteriorly ; 

 aperture oblique, bluish-white within ; peristome flesh-colored, very 

 heavy and thick, expanded, its face convex, bearing on the inner 

 margin numerous tubercular teeth; umbilicus closed bv the ex- 



O V 



panded baso-columellar lip or open ; parietal wall bearing a heavy 

 callus. Alt. 30, diam. 60 ; alt. 22, diam. 50 mill. 



Jurisdiction of Baracoa, Cuba. 



Polydontes imperator MONTF. Conch. Syst. ii, p. 155. If. imperator 

 PFR., Mouogr. i, p. 302 ; Novit. Conch, iii, p. 369, t. 85, f. 1-6, t. 86, 

 f. 1-6. REEVE, Conch. Icon. f. 757. FERUSSAC, Hist., t. 52, f. 4 ; t. 

 52 B, f. 1-3. ARANGO, Fauna Mai. Cubana, p. 75. H. magica 

 FER. Hist. t. 54 A, f. 7-9. PFR., Monogr. i, p. 302. 



A fine large species, unlike any other. If anything like Ferussac's 

 H. magica (pi. 8, figs. 77-79) ever existed, it may have been a form 

 of H. imperator. 



H. APOLLO Pfeiffer. PL 9, figs. 84-86. 



Imperforate, depressed, very solid, opaque, lusterless, above, shin- 

 ing below ; clear yellow, or with russet spiral lines above ; surface 



