326 
STOASTOMA §. 4. 
convexi, ultimus vix solutus; apertura semicirculo paulo major, 
pone labrum subcontracta ; labrum superne abrupte productum, 
carinis vix crenulatum; labium valde solutum, subreflexum; 
umbilicus latiusculus, lamella spirali mediocri. — Operc. pro- 
funde concavum, laevigatum, utrinque auriculatum. — Diverg. 
140°; long. 0,045; lat. max. 0,086; lat. min. 0,07 poll. (Ad.) 
Stoastoma Tappanianum Adams in Ann Lyc. N.-York. V. N. 2. p. 65. 
— — Adams Contrib. to Conch. N. 8. p. 149. *) 
Habitat in insula Jamaica. 
541 16. Yilkin§oniae Adams.f 
T. subdiscoidea, carinis 5 et lineis spiralibus subtilissimis 
(4 — 6 in quovis interstitio) sculpta , pallide cornea , subdia- 
phana; spira modice et convexe elevata; anfr. 3 r /. 2 angulati, 
ultimus latiusculus, antice solutus; apertura campanulata; 
labrum longe productum, auriculatum, carinis profunde cre- 
natum; labium valde solutum, subreflexum; umbilicus latius- 
culus, lamella spirali mediocri. — Operc. utrinque auriculatum, 
subtilissime punctulatum. — Diverg. 140° ; long. 0,035 ; lat. 
max. 0,07 ; lat. min. 0,055 poll. (Ad.) 
Stoastoma Vilkinsoniae Adams in Ann. Lyc. N-.-York V. N. 2. p. 64. 
— — Adams Contrib. to Conchol. N. 8. p. 148. **) 
Habitat in insula Jamaica. 
542 17. St. HolIatidSatmm Adams, f 
T. subdiscoidea, carinis 5 et lineis subtilissimis spiralibus 
(plerumque 3 — 6 in quovis interstitio) sculpta, pallide cornea, 
subdiaphana; spira modice et convexe elevata; anfr. 3*/ 2 
modice convexi, subangulati, ultimus antice vix solutus; aper- 
tura majuscula, pone labrum leviter constricta; labrum modice 
productum, carinis vix crenulatum; labium liberum, vix re- 
flexum ; umbilicus latiusculus , lamella spirali mediocri. — 
Operc. subauriculatum , laevigatum. — Diverg. 145°; long. 
0,035 ; lat. max. 0,065 ; lat. min. 0,055 poll. (Ad.) 
*) This shell resembles S. Gouldianum , and might be mistaken for 
the young of that species. But the labrum is thickened as in all mature 
shells of Stoastoma proper. It is most readily distinguished by the peculi- 
arities of the aperture. (Adams 1. c.) 
**) This shell closely resembles S. Gouldianum , and is most readily 
distinguished by the difference in size. A closer inspection will detect the 
more essential differences. (Adams 1. c.) 
