THE NAUTILUS. 



VOL. XI. OCTOBER, 1897. No. 6. 



NEW LAND SHELLS FROM MEXICO AND NEW MEXICO. 



BY W. H. DALL. 



Holospira (Haplostemma) Cockerelli n. sp. 



Shell small, pupiform, blunt-tipped, with two smooth nuclear and 

 about a dozen subsequent whorls ; those following the nucleus are 

 rather strongly obliquely ribbed with close set fine riblets which be- 

 come fainter over the main body of the spire and reappear again on 

 the last whorl ; aperture entire, simple, rounded, but a little angular 

 at the posterior outer corner ; the umbilicus closed, the spire grad- 

 ually enlarging to the eleventh whorl, then slightly attenuated. Alt. 

 12'5, max. diam. 3'2 mm. 



Found in the debris of the Rio Grande at Mesilla, New Mexico, 

 by Prof. Cockerell. 



This is the second species of Haplostemma, and one of the small- 

 est, if not the smallest, Holospira yet recorded. It forms an addi- 

 tion to the fauna of the United States. 



Eucalodium hippocastaueum n. sp. 



Shell of moderate size, with 8 (decollate) whorls, the penultimate 

 the largest, thence gently tapering to the decollate apex ; surface 

 very dark chestnut brown covered with fine, slightly wavy, close 

 set riblets accompanied by fine axial wrinkles near the sutures, a 

 few irregular spiral threads occasionally appear, suture distinct, 

 umbilicus closed, a faint keel below the periphery of the last whorl, 

 aperture simple, rounded, the peristome slightly thickened, not re- 

 flected. Alt. 32, max. diam. 9*2, aperture 8 mm. 



