250 MAZATLAN UNIVALVES 



GEips GLOBULUS, Schum. 



Schumacher, Essai <$fc. 1817, no. 23 : (non Soiv.). Phil. Handb. 



Condi, p. 208. 



Ttotella, Lam. 1822, et auct. 

 Umbonium, Link; A. Ad. Mon. in Proc. Zool. Soc. 1853, 



p. 187 : H. $ A. Ad. Gen. vol. i. p. 407. 

 Pitonellus, Montf. 

 Helicina, (Lam. a" prima manu) Gray in Proc. Zool. Soc. 



1847, p. 145. 



317. ? GLOBULUS TUMENS, n. s. 



? G. t. globosd, solidiusculd, alba, subnitente ; spird planatd, 

 depressd, anfractibus iv. suturd hand impressd ; striulis spira- 

 libus subobsoletis teiiuissime ornatd ; callositate valde tumente, 

 trientem partem basis tegente, suturd impressd, -mnbilicum 

 tegente, in parietem et inius suturam spiralem ascendente, juxta 

 labium vix planatum ; aperturd intus rotundatd, labro in 

 spiram ascendente. 



This species is intermediate between the typical Globnli and 

 the Ethalioe. In the faint sculpture and slight planing off of 

 the callosity, it presents the characters of the latter genus ; 

 in the large swelling growth of the callus, which appears glossy 

 over the whole surface, and covers the body whirl within the 

 mouth, running up to the suture, it is a true Globulus. Two 

 older specimens were found, sufficiently agreeing in other 

 respects, but displaying a groove in the callus near the base of 

 the columella, exactly in the same place, which is remarkable 

 if accidental. They are both however worn specimens. If it 

 should prove a constant character, they may take the name 

 of "G. sulcatus, t. callo basim versus subprofunde sulcato." 

 Long. '013, tot. "038 by '033, div. 160. 

 Hal). Mazatlan ; 3 sp. off Chama and Spondylus ; L'pool Col. 



Tablet 1168 contains the fresh specimen, andjone of the form 

 G. sulcatus. 



SUBGENUS ETHALIA, H. fy A. Ad. 



Gen, vol. i. p. 409 : Proc. Zool. Soc. 1853 (Mon. Umb.) p. 189. 



A small group of Mazatlan shells, of the general aspect of 



Vitrinellee, and agreeing with Globulus in having a callous base, 



