ZONITES. 



121 



Orono, Maine. I find 19 1 19 teeth, with 3 laterals. I doubt there being 

 any inner cutting points to the lateral teeth, as observed by Mr. Morse on the 

 lingual examined by him. 



In Am. Journ. Conch. I. 188, Mr. Tryon proposes for this species the name 

 ]\Iorsei, on account of Helix Binneyana, Pfr. I have retained Morse's name, as 

 it is not preoccupied in the genus Zonites. In his first catalogue of Maine 

 Shells, Mr. Morse uses the name Binneyi, which can be employed, if necessary, 

 to distinguish the species from Pfeiffer's. 



Genitalia not observed. 



Zonites ferreus, MORSE. 



Shell umbilicated, depressed-globose, transparent, of a very light steel-gray 

 color, not shining, marked with very delicate incremental wrinkles and micro- 

 scopic revolving lines ; spire slightly elevated ; whorls 3, 

 rounded, the last rapidly enlarging, globose ; aperture large, Fi s- 37. 



transversely subcircular; peristome simple, acute, its ex- 

 tremities not approaching, that of the columella scarcely sub- 

 reflected. Greatest diameter, 2i mill. ; height, 1 j mill. z. ferreus. 



Striatura ferrea, MORSE, Proc. Portl. S. N. H., I. 17, Figs. 36-40, and H. II. 



Fig. 10 (1864). 

 Ilyalinn ferrea, TRYON, Amer. Journ. Conch., II. 253 (1866). W. G. BINNF.V, 



L. & Fr.-W. Sh., I. 40 (1869). GOULD and BINNEY, Invert, of Mass., ed. 2, 



401 (1870). 

 Helix ferrea, MORSE, Amer. Nat., I. 544, Fig. 37 (1867). 



Fig. 38. 



Jaw of Z. ferreus (MORSE). 



Maine : a species of the Northern Region. 



Jaw angularly arched, ends ta- 

 pering, acute ; anterior surface 

 deeply channelled in its centre ; 

 concave margin smooth, with a 

 deep, median indentation, probably 

 worn by the greatly developed cen- 

 tral tooth of the lingual membrane. 



Lingual membrane with 39 curv- 

 ing rows of 20 1 20 teeth ; centrals enormously developed, very broad, 

 tricuspid, the middle cusp very broad ; two bicuspid laterals on each side, 

 the inner much the smaller ; marginals aculeate. Another membrane (PI. III. 

 Fig. P), had also 20120 teeth, with 2 perfect laterals. 



Genitalia unobserved. 



Zonites conspectus, BLAXD. 



Shell umbilicate, subdepressed, thin, with oblique, rather distant rib-like 

 striae, the interspaces microscopically striate, dark horn-colored ; spire convex, 

 with smooth, obtuse apex; suture deep; whorls 4, convex, gradually increas- 

 ing, the last broader, rounded, slightly descending above; umbilicus about 



