472 MAZATLAN UNIVALVES 



f. 25. Duel Monogr. 01. pi. 1, f. 3, 4. Eve. Conch. Ic. 



pi. 29, f. 91. 

 Olivella zonalis, H. fy A. Ad. Gen. i. 146. 



The O. mutica, as figured by Duclos, more nearly resembles 

 this than No. 598. It is distinguished in colour by two distinct 

 purple brown bands on the back, with a deep stain on the 

 parietal and another on the basal callosity. The diffused hue 

 is light or dark, with the same variation on the spire, and 

 yellowish below the suture. Spire more or less acuminated. 

 Mouth very open. Columella as it were excavated, smooth ; 

 with one sharp, winding plait, bounding the siphonal notch. 

 Long. '32, long. spir. '13, lat. *15, div. 50. 



.Zfo&. Acapulco, Humboldt fy Bonpland. Mazatlan ; ex- 

 tremely rare ; L'pool Col. 



Tablet 2198 contains 3 specimens varying in colour. 



GENUS AGABONIA, Gray. 



Zool. Beech. Voy. 1839, p. 131. #". $ A. Ad. Gen. vol. i. p. 142. 

 Hiatula, Swains. Oliva, pars, auct. 



602. AGAKONIA TESTACEA, Lam. 



Oliva testacea, Lam. in Ann. Mus. vol. xvL 1810, p. 324, 



no. 51 : An. s. Vert. vol. x. p. 627, no. 51. VaL in Humb. 



Rec. Obs. vol. ii. p. 334. Duel in Chenu Conch. III. pi. 3, 



f. 17, 18, (f. 19, 20, excl., teste C. S. Ad.) Eve. Conch. Ic. 



pi. 18, f. 36. Mice, in Zeit. f. Mai. 1851, p. 25, no. 108. 



C. B. Ad. Pan. Shells, no. 38, p. 54. 

 Agaronia testacea, T. fy A. Ad. Gen. i. 142, 

 = Oliva hiatula, pars, Duel. Mon. Oliv. pi. 3, f. 15, 16. Non 



Lam. An. s. Vert. vol. x. p. 627, no. 52. 

 Agaronia hiatula, [Gray, non] Lam. Zool. Beech. Voy. p. 132. 



Having very carefully examined many hundreds of Mazatlan 

 specimens, and compared them with a series sent from the 

 Gambia by Chief Justice Eankin,* and also with the Bordeaux 

 fossils assigned to O. hiatula by Deshayes and Duclos, it would 

 appear that the judgment of Lamarck can be maintained 



* Of this valuable and very reliable collection, which I had an opportunity 

 of examining on its first arrival, the principal part is to be found incorporated in 

 the general Museum of the Bristol Institution. 



