MAZATLAN UNIVALVES 461 



GENUS STBIGATELLA, Swains. 



Treatise, &c. 1840. 



Mitra, pars, auct. Shell Collambelloid. 



/ 



+ 586. STRIGATELLA TEISTIS, Brod. 



Mitra tristis, Brod. Proc. Zool. Soc. 1835, p. l^.Eve. Conch. 



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

 Strigatella tristis, H. $ A. Ad. Gen. i. 174. 

 = Mitra amphorella, P. P. C. Cat. Prov. nonLam. 



There are 4 distinct columellar plaits, with one rudimentary 

 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 measures long. I' 2, long. spir. '47, lat. *58, div. 50. 

 An acuminate sp. *9, *4, *35, 40. 



A broad sp. '95, '34, '45, 60. 



Hab. 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 MAKGINELLID.E. 

 j^ 587. MAKGINELLA MJNOK, C. B. Ad. 



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



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



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

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

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

 being narrower at! the shoulder. 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- 



