HELIX-LUCERNA. 103 



H. nannodonta A. D. Brown mss. is a form similar to goniasmos, but 

 with a second tooth developed near the columella. Both teeth are 

 tubercular. The type is figured on pi. 26, fig. 62. Ferussac's figures 

 of H. lamarckii var. unidentata (Histoire, t. 58, f. 1, 2) are probably 

 referable to H. patina, or to a form intermediate between patina 

 and typical acuta. These figures are copied on my pi. 33, figs. 3, 

 4,5. 



I would retain H. patina separate from H. acuta, on account 

 of the single basal tooth, which is tubercular, not compressed, were 

 it not connected directly by intermediate examples with acuta. H. 

 patina often has two basal teeth ; both are small ; they are rather 

 separated. 



Var. OXYTENES A. D. Brown (mss). PI. 55, figs. 4, 5. 



Still more depressed than H. patina ; periphery compressed into 

 a knife-like carina ; base of the aperture with one or two small 

 teeth ; borders of the whorls a trifle undulating, but much less so 

 than in H. chemnitziana. Alt. 20-23, diam. 53-58 mill. 



Var. INGENS C. B. Ad. PL 27, fig. 80. 



Much depressed, especially above; carina acute, compressed, 

 concave above and below ; teeth of the basal lip generally two, stouter 

 and nearer together than in H. patina and compressed, acute, not 

 tubercular. The inner tooth often has one or more small denticles 

 near it as in H. chemnitziana. The borders of the whorls are often 

 somewhat uneven above, but not distinctly undulating. The color 

 varies from a yellowish-flesh tint to deep chestnut-brown ; light 

 specimens have dark inner whorls. The umbilicus is generally 

 covered by expansion of the lip. Lip and aperture white, flesh- 

 tinted or brown. Alt. 30, diam. 65 mill. ; often greater or less. 



H. ingens C. B. AD. Contr. to Conch, no. 5, p. 76 ; no. 9, p. 170. 

 REEVE, f. 221. PFR. Monogr. iii, p. 214. 



Var. NOBILIS C. B. Adams. PI. 26, figs. 59, 63, 64. 



Shell transversely ovate-orbicular, moderately and irregularly con- 

 vex above, regularly and very convex beneath ; above reddish or 

 blackish brown, with paler spaces; beneath with a broad belt of 

 blackish-brown next to the periphery, within which the shell is of a 

 bright yellowish-green ; lip purple, irregularly spotted with white ; 

 surface rather feebly granulated, smooth near the apex and umbilical 

 region, the lower part of the whorls for the most part undulated by 

 short oblique impressions ; spire moderately elevated ; w y horls a little 



