CANARIAN GROUP. 475 



singularity of structure, combined with its less circular aper- 

 ture (or less continuous and less elevated peristome), and its 

 shorter and less convex subapical whorls, will, apart from other 

 features, altogether separate the species from the European G. 

 elegans,a,s well as from the sulcatum, Drap., the siculum, 

 Sow., and other members of that Mediterranean type. In 

 colour the C. canariense varies from a bleached yellowish 

 white into a dark leaden brown, passing through a clear reddish- 

 testaceous state into one which is adorned with three (sometimes 

 dark and sometimes pallid) bands ; but these hues are so little 

 characteristic of the particular phases which are brought about 

 by a change of sculpture that it is scarcely worth while to at- 

 tempt to make use of them in enunciating the latter. Perhaps 

 therefore the following short diagnoses of the principal varieties 

 which are now before me may suffice to place on record what I 

 would regard as at any rate some of the most important aspects 

 of this truly protean Cydostoma. 



a. palmensis. Magnus, costis spiralibus alte elevatis, 

 lineolis intermediis longitudinalibus confertis regularibus cur- 

 vatis ; suturse lamella late appressa, valde irregulariter sed parce 

 lacerata. [ins. Palma, in Barranco de Harradura a Rev. R. T. 

 Lowe lectusJ] 



(3. raricosta. Magnus, costis spiralibus altissime et subito 

 elevatis sed latiusculis, lineolis intermediis longitudinalibus sub- 

 obsoletis ; suturse lamella paulo minus late appressa, ac densius, 

 profundius, magisque regulariter dentato-lacerata. \_ins. Tene- 

 riffse sylvatici editiores ; in montibus supra Taganana sat 

 vuigaris.~\ 



7. incequalis. stat. @. magnitudine formaque similis, sed 

 costis spiralibus minus elevatis ac (praecipue in anfractibus pos- 

 terioribus) magis numerosis necnon subinsequalibus, lineolisque 

 intermediis longitudinalibus confertissimis subregularibus sub- 

 rectis. [ins. Teneriffae regiones minus elevatce, juxta Portum 

 Orotavce in statu vix semifossili abundans.~\ 



8. lanzarotensis. Subminor, costis spiralibus paulo mino- 

 ribus minusque elevatis, lineolisque intermediis longitudinalibus 

 in anfractibus anterioribus confertis regularibus subrectis, sed 

 in posterioribus magis remotis ac magis conspicuis, foveolas 

 intermedias longitudinales punctiformes efficientibus ; suturae 

 lamella plerumque minus lacerata. [ins. Lanzarota ; in decli- 

 vibus prceruptis excelsioribus supra ' Salinas,' necnon sec. Dom. 

 Webb in ins. parva adjacente ' Grraciosa ' dicta, congregans.~] 



s. adjunctus, Mouss. stat. S. fere similis, subtenuis, ple- 

 rumque leetius coloratus minusque opacus, costis spiralibus 

 minus elevatis sed etiam submagis numerosis necnon in anfrac- 

 tibus anterioribus interdum evanescentibus ; sed lineolis longi- 



