246 



SOLARIUM. 



(p. 323, n. 1485) : — "Testa crenato-umbilicata, convexa, obtusa, 

 marginata, longitudinaliter crenato-striata." It is said to come from 

 the Indian seas, and only to differ from bis perspective (the syno- 

 nymy of which includes irochleare, and almost all the then known 

 allied species) by its contiguous, longitudinal, crenated striae. 



Genus BIFRONTIA, Desh. 



Gen. Char. Discoidal, planorbular, paucispiral, keeled above 

 and below; body-whorl slightly detached; apex sunken ; mouth 

 squarish; no umbilicus; operculum externally conical, truncated at 

 the top. 



1. Zancl^ea. (Bif. f. 1, 2), Phil. — T. parva, tenuis, discoidea, 

 fulva (ssepius colore saturatiore et pallidiore alterne nebulosa), 

 supra plano-concava, infra coneava. Anfractus pauci, laxati 

 (plerumque ad aperturam, apicemque, disjuncti), cingulo confertiin 

 squaraoso-granoso, superne et interne utrinque marginati ; alibi 

 lseves, nitidi, et (area latissima subplanu inter peripheria; carinas 

 2 excepta) convexi. Cingulum interius multo minus ; c. exte- 

 rius, in anfractu ultimo carinam valde eminentem simulans. 

 Apertura subquadrata ; labium continuum, haud reflexum, sculp- 

 ture expers. Obs. None of my specimens exhibit the peripherial 

 threads delineated (pi. 28, f. 11a), but not described, by Pbilippi. 

 The operculum is of a truncated conic shape and subconcentri- 

 cally lamellar; it is very like that of Torinia. The entire shell is 

 enveloped by a dull epidermis, which at times is so wrinkled, that 

 the periphery seems spirally striated. One or both of the keels 

 is here and there obscurely cloven. 



INDEX. 



The synonyms are in italics. 



.Kthiops, Menhe, 30, f. 68, 69, 70. 



Architse, Costa, p. 245. 



<7ra>/fl,Gmel. = perspectiviuncuhis. 



asperum, Hinds, 35, f. 77, 78. 



australe, Pliil.= perspectivum. 



Bairdi, Hani. 9, f. 48, 49. 



biangulatum, Gray (Appendix, 

 King's Australia). — Not a So- 

 larium (" nacreous"). 



bicanaliculatum, J'al., p. 237. 



bicarinatum, Phil., p. 245. 



bisulcatum, D'Orb., 27, f. 71, 72. 

 cancellatuin, Krauss (Siid-Afrik. 



Concli. 95, pi. 5, f. 2!)).— Not 



a Solarium. 

 Chgmnitzii, Kien. = infundibuli- 



forme, var. 

 cingulum, Kien., 24, f. 55, 56. 

 cselatum, Hinds, 33, f. 75, 76. 

 cratera, Scrramach. (193, for 



Chemn. f. 2065, 66), is Helix 



Turcica. 



