MAZATLAN UNITALVES 



36^ 



the whirls more regularly divergent, and not so tumid towards 

 the end. This has the same kind of sculpture on the nucleoid 

 whirls, but is wanting in the spiral line which is characteristic 

 of the Mazatlan shell. An adolescent sp. with three subnormal 

 whirls, measures long. "067, long. spir. '01, lat. "035, div. 30". 

 The largest „ '19, „ -125, „ -075, „ 22". 



Hah. — Mazatlan ; very rare, on Chama and Spondylus ; 

 L'pool Col. 



Tablet 1723 contains a young sp., the most perfect adult, and 

 a broken sp. with the nuclear portion distinct. 



426. Alaba violacea, n. s. 



A. t. solidiore, conicd, Icsvi ; anfr. pnmis leBvibus, tumidis, 

 violaceis, pavum divergentihus, liaud planatis, suturis impressis, 

 albidis ; peripheria vix angulaid, umhilico nullo ; swperfide 

 transversim minutissime rugulosd. 



This shell has unfortunately lost its apical whirl, and the 

 last ; but the characters are suiScicntlj^ distinct. It differs from 

 A. supralirata in the smoothness and tumidity of the tuberose 

 whirls ; and in the extremely minute corrugation of the other- 

 wise smooth surface, in which it agrees with A. mutans and 

 PChrysallida clausiliformis. The specimen has three normal 

 whirls ; and measures (allowing for the apex) lo7ig. '06, long, 

 spir. -037, lat. '032, div. 35". 

 Sah. — Mazatlan ; 1 sp. off Spondylus ; L'pool Col. 



Tablet 1724 contains the specimen. 



427. Alaba teeebkalis, n. s. 



A. t. solida, conica, apicem versus acutissime terebrante, albo- 

 fmcA, l(Bvi ; anfr. primis parum rotundatis, maxime elongatis, 

 angmtissimis, marginibus pcene parallelis ; anfr. normalibus 

 planatis, suturis haud monstrantibus, marginibus spirce dilor 

 tantihus ; basi parum rotundatd, umbilico nullo. 



The only specimen found is in a similarly imperfect state 

 with that of the last species ; from which it differs in the great 

 elongation of the less swollen tuberous whirls, and in the 

 Eulima-hke aspect of the flattened normal whirls. Of these 

 there are four; and the specimen measures long. '067, long^ 

 spir. -04.5, lat. "03, div. 40". 

 Hob. — Mazatlan ; 1 sp. off Spondylus ; L'pool Col. 



Tablet 1725 contains the specimen. 



