MAZATLAN UNIVALVES 435 



lat. *027, div. 18°. Mr. Hanley however found four specimens, 

 each with five whirls, the largest of which measures ' 113 by '037. 

 Sah. — Mazatlan ; extremely rare, off Spondylus ; L'pool 8f 

 Havre Coll. 



Tablet 2008 contains the youngest sp. ; and an adult, present- 

 ed by S. Hanley, Esq. 



538. DtTNKEEIA CANCELLATA, n. S. 



D. t.juniore effusa, riifo-fuscd, anfr. normaUbus ii et dimidio, 

 valde tumentibus, vix attlngentilnis, superne angulatis ; vertice 

 nucleoso iumcnte, heUcoideo, anfr. ii. verticaUter sifts ; lirulis 

 plurimis transversis acutissimis, et spiralibus minorihus elegau' 

 tissime cancellatd ; labro angulato ; labio rimulam umbilicalem 

 circumeunte ; plica columeUari nulla,. 



This exquisitely beautiful young sheU looks like an elongated 

 Cancellaria without plaits ; it is shouldered as in C. goniostoma. 

 The sinistral apex is very prominent. When adult, it must be 

 of surpassing elegance. Long. "038, lo7ig. spir. 'QQ, lat. '02, 

 div. 15". 



JSah. — jVIazatlan ; 1 young sp. off Spondylus ; L'pool Col. 



Tablet 2009 contains the specimen. 



539. DtTNKESIA INTEEMEDIA, n. S. 



D. t. albd, elongatd, tenui : vertice nucleoso maximo, anfr. iii. 

 helicoideis, verticaUter sitis, promhientibus, apice conspicuo, 

 marginibics spirce superantihus ; anfr. primis normaUbus con- 

 vexis, dein subplanatis ; striis spiralibus omnino ornatd, tenui- 

 bus, ohtusis, quariim circiter vii. in spird apparent; striulis 

 tenuibus minorihus transversis evanescentibus vix dectissatd ; 

 interdum, lirulis evanescentibus irregularibus ; hasi subelongatd; 

 aperturd ovali ; columelld vix contortd. 



This species is described, although from a single yoTing 

 specimen and a broken adult, in cousequencp of its aberrant 

 scidpture, which is more appropriate to Aclis, while the shape 

 of the aperture is characteristically Cheranitzian. The trans- 

 verse ridges are only represented, in the young shell by very 

 faint threads, most conspicuous at the sutures, while the spiral, 

 somewhat flattened lines are prominent. The young specimen 

 has only 3 normal whirls, and measures long. "055, lat. '027, 

 div. 12°. The adult, which has lost the lower whirls, has the 



