MAZATLAN UNIVALVES 253 



322. ETIIALIA AMPLECTANS, n. s. 



JE. t. minimd, planald, diaphand, nitidissimd ; anfractibu-s 

 iii, planatis, peritremati rotundato ; callositate haud parvd, 

 umbilicum vix tegente, juxta labium planatd, semilunatd ; labro 

 acuto, supra anfractum penultimum dilatato ; infra sutwam 

 Jiaud impressam callositate, suturamfallacem extus simulante ; 

 aperturd rotundatd. 



As it is barely possible that this shell may be the young of 

 Teinostoma amplectans, the same specific name has been given. 

 It differs however in the much smaller size of the callosity, 

 which in this shell displays a broad, semi-lunate planation at 

 the columella, which appears characteristic of the species. 

 Long. '016, lat. '04 by '032, div. 180. 

 Hob. Mazatlan ; 4 sp. off Spondylus ; Epool Col. 



Tablet 1173 contains the freshest specimen. 



GENTJS TEINOSTOMA, A. Ad. 



Proc. Zool. Soc. 1853, p. 183. H. $ A. Ad. Gen. vol. i. p,122. 

 Testa spird depressd, politd, anfractibus rapide augentibus ; 

 regione umbilicali callosd ; aperturd productd, elongatd, ab axi 

 remotd ; interstitio calloso ; peritremati axin versus rotundato, 

 ad peripheriam interdum angulato. 



Shell Eotelloid, with a greatly produced mouth and callus. 

 It resembles Cyclops among the Nassidse, and in the appear- 

 ance of the base reminds the observer of Streptaxis and 

 Anostoma among the Helicidae. Having been described (in 

 English only) from a single species (T. politum, St. Elena, 

 8 fm. Cuming,) some of the characters before given may here- 

 after prove to be only specific. 



323. TEINOSTOMA AMPLECTANS, n. s. 



T. t. parvd, albd, planatd, Icevi ; peritremati rotundatd ; 

 callositate spirali umbilicum tegente, labium versus subplanatd t 

 fupra parietem intus suturam decurrente ; aperturd rotundatd ; 

 labro supra anfractum penultimum rejlecto ; suturd haud 

 impressd. 



Although the shells described above as Ethalia may possibly 

 be the young of this species ; yet, as they were all of the sam* 

 June 1856. y 



