304 
4. A MonoGRAPH OF THE GENERA REALIA AND HYDROCENA. 
By Dr. L. PFeirrer. 
These two genera are closely allied by the common character of 
the ovate, few-whorled, horny operculum, but they may be separated 
by the characters of the mouth and columella. 
I. Reawia. 
Gray, in Proc. Z. 8. 1847, p. 182; & 1849, p. 167; Pfr. Consp. Cycl. 
p- 47; Mon. Pneumonoph. p. 305. 
Liarea, Gray, Cat. Phaneropneum. Br. Mus. p. 217. 
Shell turreted, rather smooth or striated ; aperture ovate ; peri- 
stome continuous, double. 
1. Reaxia Eera, Gray, 1849; Pfr. Mon. Pneum. p. 305. 
Tiarea Egea, Gray, 1852. (New Zealand.) 
2. ReaLiA TURRICULATA, Pfr. R. testa subperforata, gracili, 
turrita, solidula, striatula, parum nitente, nigricante, fascia pallida 
basali notauta vel strigis angulosis nigro-castaneis et luteo-albis 
alternantibus ornata, basi nigricante ; spira elongata, apice ob- 
tusula ; anfract. 7-73 modice convewis, ultimo 4 longitudinis sub- 
equante, basi obsolete subangulato ; apertura verticali, angulato- 
ovali ; perist. continuo, duplice : interno breviter porrecto, externo 
anguste expanso, inflexo. 
Long. 9, diam. 32 mill. 
Hab. New Zealand. 
3. Reauia venTRicosa, Hombr. and Jacq. (Cyclostoma ventri- 
cosum, H.et J. Voy. Pole Sud, Atl. t. 12. f. 34-367) R. testa 
subperforata, turrito-oblonga, tenuiuscula, sub lente confertissime 
striata, vir nitidula, fusca vel cornea; spira elongata, subventri- 
cosa, apice acutiuscula ; anfract. 7 conveais, ultimo 4 longitudinis 
subequante, infra medium obsolete angulato; apertura parum 
obliqua, ovali; perist. continuo, indistincte duplicato, margine 
dextro expansiusculo, sinistro strictiusculo, adnato. 
Long. 7, diam. 3 mill. 
Hab. Taiti (Jacg.); Marquesas Islands (Hl. Cuming). 
4. ReALIA RUBELLA, Pfr. R. testa subperforata, turrito-oblonga, 
solida, levigata, pallide rubella; spira elongata, superne atte- 
nuata, acuminata, sutura profunda ; anfract. 8 convexis, quasi 
strangulatis, ultimo 4 longitudinis non attingente, obsolete angu- 
lato; apertura vie obliqua, angulato-ovali; perist. continuo, 
breviter adnato, duplicato : externo subincrassato, patente. 
Long. 8, diam. 3 mill. 
Hab. Marquesas Islands (H. Cuming). 
