THE NAUTILUS. 99 



pyrgus) Habeli. This species is distinguished from B. (P.) Chem- 

 nitzioides by its nearly smooth polished surface, light-brown spiral 

 bands on a white ground and usually more slender form. It has 

 about fifteen whorls, a blunt apex and rounded base. It measures 

 18'0 by 3'5 mm. It was also collected on Chatham Island by the 

 U. S. S. Albatross on her late voyage from Norfolk to San Francisco. 

 It does not appear among shells enumerated by Wimmer from the 

 Habel Collection in his catalogue of the Galapagos mollusk-fauna. 



A NEW SPECIES OF ZONITES FROM ARKANSAS. 



BY H. A. PILSBRY. 



Zonites Brittsii n. sp. 



Shell imperforate, depressed, obtusely angled at the circumference, 

 about equally convex above and below. Color yellowish-green, 

 somewhat translucent, becoming light straw-yellow and opaque on 

 the last fourth of the last whorl. Surface shining, having oblique 

 striffi under the sutures, the growth lines being quite light on the 

 rest of the surface ; base seen under a lens to be very densely con- 

 centrically striated. Whorls 6. Base slightly indented at the axis. 

 Aperture slightly oblique, depressed-lunar, the outer and basal tvalls 

 lined with a heavy, opaqae-tvhite calcareous layer. 



Alt. 5, greater diam. 8"5, lesser 7*7 mill. Aperture, oblique alt. 

 4, width 5*6 mm. 



Hot Springs, Arkansas. 



This species was collected by Mr. John H. Britts, and sent by 

 him to the collection of the American Association of Concholo gists, 

 where the types may now be seen. They were submitted to the 

 writer by the President of the Association. 



The more prominent characters of this shell are its imperforate 

 base, depressed, almost quoit-like form, the base closely concentric- 

 ally striated, the shining surface, and the contrasting colors of the 

 last whorl. 



Mr. Britts sent also, specimens of the rarely found 3-toothed form 

 of Helix appressa Say, from Booneville, Mo., and a number of other 

 interesting shells. 



