MAZATLAN UNIVAIVES 461 



Genus STEIGATELLA, Swains. 



Treatise, &c. 1840. 



Mitra, pars, aiicf. Shell Collambelloid. 



586. Steigatella teistis, B)'od. 



Mitra tristis, Brod. Proc. Zool. Soc. 1835, p. 194.— i?ye. Co7ich, 



Ic. pi. 15, f. 114— C. B. Ad. Pan. Shells, p. 44, no. 20. 

 Strigatella tristis, H. 8f A. Ad. Gen. i. 174. 

 = Mitra ampliorella, P. P. C. Cat. Prov. non Lam. 



There are 4 distinct columellar plaits, with one rudimeutarj' 

 in the adult. In very young shells, only three are seen. There 

 is no sculpture except some faint spiral lines, and very irregu- 

 lar swellings of growth. The shoulder is more or less swollen 

 with a light band more or less developed.. The largest speci 

 men measui-es lone/. V2, long. spir. '47, lat. "58, div. 50" 

 An acuminate sp. „ '9, „ '4, „ '35, „ 40" 



A broad sp. „ -95, „ '34, „ -45, „ 60« 



Sab. — St. Elena and Galapagos ; in sandy mud, 6 — 10 fm 



Cuming. — Panama ; very rare, under stones near low water 



mark ; C. B. Adams. — Mazatlan ; not uncommon, generally 



incrusted ; L'pool Col. 



Tablet 2100 contains 3 sp. very acuminate. — 2101, 4 do. spire 

 elevated,— 2102, 5 do. normal state.— 2103, 4 do. broad form.— 

 2104, 2 sp. after acid, shewing colour. — 2105, 2 sp. much 

 encrusted with coralline and Bryozoa.— 2106, 3*sp. mended 

 after fracture. 



Family MAKGJjS'ELLID^. 



587. MAEaiNELLA MINCE, C. B. Ad. 



Pan. Shells, pp. 40, 304, no. 40. 



Gibberula (Persicula) minor, H. Sf A. Ad. Gen. i. 193. 



This species is stated by Prof. Adams to be the analogue of 

 the W. Indian M. Lavalleana, D'Orh. B. M. Cat. Cub. Moll. 

 p. 25, no. 282, ( = M. minima, Guild.) from which it differs in 

 being narrower at,the shoiUder. About 200 specimens were 

 found on shells, but mostly young or imperfect. It is extremely 

 glossy, never horn-coloured when fresh, white, nearly trans- 

 parent, in shape somewhat like M. sapotilla ; with two pro- 



