1225 



VOLUTION. 



VOLUTID/E. 



1220 



powerful agents iu keeping to her Molluica and Conchifera within due 

 limits. 



^The genus Valuta stands, in the last edition of the 'Systema 

 Naturae,' revised by Linnaeus, between the genera Sulla and Buccinum, 

 with the following definition : Animal, a Limax, or Slug. Shell 

 unilocular, spiral. Aperture ecaudate, subeffuse. Columella or pillar 

 plaited. No labium nor umbilicus. 

 Linnaeus thus subdivides the genus : 



* Aperture entire. 



Species: V. Aura Afida, Auris Judcf, tornatilis, solidula, limda, 

 and co/ea. 



'* Cylindroid (subcylindrical and emarginate). 

 Species : V. porphyria, oliva, and itpidula. 



'* Ovate (obovate, effuse, emarginate). 



Species: V. dactylus, miliaria, monUi, persicula, pallida, faba, 

 glabclla, reticulata, mercatoria, rustica, paupercula, mendicaria, and 

 cancdlata. 



*** Fusiform. 



Species : V. tringa, coi-niculala, virgo, scabricula, ruffina, sanguisuga, 

 caffra, morio, vulpecula, plicaria, pertuta, mitra, mulica, vespertilio, 

 cbraa, turlinellut, capitellum, ceramica, pyrum, and lapponica. 



***** Ventricose. 

 Species : V. JSthiopica, cymbium, and olla. 



The species belonging to the Linnaean genus Valuta, when Lamarck 

 published his ' Animaux san Vertebres,' amounted to nearly 300, 

 and they would be now considerably above that number. Some of 

 these species are even referred to other families. 



The following is a definition of the Volutidce as at present con- 

 stituted : Shell turreted or convolute; aperture notched in front; 

 columella obliquely plaited; operculum absent. Animal with a 

 recurved siphon; foot very large, partly hiding the shell; mantle 

 often lobed and reflected over the shell; eyes on the tentacles 

 or near their base; lingual ribbon linear; rachis toothed; pleura 

 unarmed. 



We give the genera of this family and illustrations of some of the 

 species : 



Valuta has the shell ventricose, thick ; spire short, apex mamilla- 

 ted ; aperture large, deeply notched in front ; columella with several 

 plaits. V. mulica and a few others have a small operculum. Animal, 

 eyes on lobes at the base of the tentacles; siphon with a lobe on each 

 side, at its base ; lingual teeth 3-cusped. 



This comprises Cymbiola and Harpula of Sowerby, Volutdla of 

 )'0rbigny, Scapha of Gray. Volutilitha aud Scaphella of Sowerby, 

 and Mela of Broderip are sub-genera. Seventy recent species and 

 eighty fossil species are known. 



V. undulata has the shell ovate-fusiform, smooth, yellowish-white, 

 clouded with fulvous or purple-black spots, ornamented with 

 numerous bay or brown longitudinal undulatingly flexuous lines ; 

 principal plaito on the pillar four ; sometimes two smaller additional 

 ones. 



It is found on the coasts of Australia, Port Western, Bass's Strait, 

 the Island Maria, Ac. 



Valuta untltilaia. (Animal and Shell.) 

 Anterior part Been from above. 



Valuta undulata. (Animal and Shell.) 

 The whole seen from below. (' Astrolabe.') 



Shell of Valuta undulata, showing the plaits on the pillar. 

 V. pacifica has the shell ovate-fusiform, anteriorly tubcrculiferous 



Vulula Pncifca, ('Astrolabe.') 



