228 SOLARIUM. 



Otherwise I should have preferred for divisional purposes, the selec- 

 tion of characters wholly based upon the shell, and independent 

 of the rarely obtained opercula. I am inclined to think that such 

 species as S. infnndiluliforme are quite as far removed from 

 Torinia as Philippia is from Archil eciomca, and that the loosely 

 coiled Bifrontia is scarcely within the limits of the genus. 



* Sect. A. Arcrtiectonica. 



1. peksfectivum (f. 36, 37, 38), Linn. — T. depresso-conica, 

 sulcis remotis validis (corpore lsevi excepto) radiatim sculpta. 

 Anfractus spiraliter unisulcati, infra suturam angustam brunnei 

 et deinde candidi (rarius subarticulati), infra sulcum spiralem 

 zona fusca ornati, deinde late fulvi seu cinerei; cingulum supra- 

 suturale rufum seu fuscum, nonnunquam albo anguste articulatum. 

 Carina angusta, fulvo remote articulata. Sulcus peripherias superior 

 perangustus et ssepius (etiamque inferior) unifilosus; areas basalis 

 medium sulcis radiatum, maculis lineisve interruptis intus margi- 

 natum. Crena) umbilici latiorisbrunnese, permulta?. — Var. (incisa, 

 Phil.). T. pallida; anfractuum zona superior, nisi in corpore, fere 

 albida; zona infra sulcum angusta, in corpore articulata; cingu- 

 lum suprasuturale brunneo et albo articulatum. Carina angusta, 

 acuta. Macule articulationesque basales ssepius pauciores et re- 

 motiores : cingulum album basale baud crasse crenatum. — Var. 

 {Ausiralis, Phil.). T. pallide cinerea; zona anfractuum superior 

 fere ut in var. prsecedente ; zona angusta, infra sulcum spiralem 

 continua. Sulci radiantes crassi et valde remoti. Cingulum su- 

 prasuturale brunneo-rufescente articulatum. Carina obtusa. Area 

 basalis media sulcis, plicisve, crassis radiata. Umbilici parvi 

 crense rnfae, satisque magna;. Obs. Not only the Linnsean type 

 of Trochus perspective, but the great majority of the synonyms 

 in the tenth edition of the ' Systema' indicate this common species. 

 Var. S. incisa, Phil., is very pale in colour, with the crenated edge 

 of the umbilicus white with light brown spots : the peculiarities 

 of his Australe are most perceptible in young specimens. 



2. trochleare (f. 19, 20), Hiuik. — T. S.perspecliro persimilis, 

 sed major, carneo-fulva ; differt etiam apice nunquam cinereo- 

 nigrescente, sulcis radiantibus magis contiguis, vitta infra sulcum 

 spiralem angustiorc (quartam partem latitudinis illius area; tantum 

 implente), et semper in anfractu ultimo articulata, sulco spirali, 

 sulco peripheriae et sulco cingulum suprasuturale praecedente latis ; 

 articulationibus carinas acutissima; brunneis, latisque; maculis in 

 media area disci inferioris magis irregularibus, flammasque simu- 



