PHILIXE. 459 



mens from the Cape of Good Hope (the original locality 

 given by Linne) , Australia, and New Zealand appear to 

 be specifically identical with those from the north of 

 ' Europe. 



Its burrow or track is not unlike the run of a 

 mole. When placed in a dish of sea-water^ its gliding 

 motion is so slow and gradual as to be perceptible only 

 by marking the distance traversed. Mr. Daniel detec- 

 ted sessile Foraminifera in its gizzard ; one now before 

 me contains an EcMnocyamus pusiUus. Sometimes the 

 plates of the gizzard, instead of being convex on the 

 inner side, become concave by the continual process of 

 shell-crushing. According to Loven the fry is enclosed 

 in a spiral shell, and swims by means of a vibratile head- 

 veil or lobe ; it is eyeless, but furnished with an oper- 

 culum ; the eggs are extremely numerous, and arranged 

 in a single row, forming a very long and loosely twisted 

 rope like a necklace ; these are enveloped in oval gelati- 

 nous and transparent capsules. Another, but less pre- 

 cise, description of the spawn has been lately published 

 in the ' Comptes Rendus ■* by Lacaze-Duthiers (who, 

 however, does not allude to Loven' s account) ; and he 

 notices some double embryos. The gizzai'd was first 

 made known and figured by Colonna, who mistook it 

 for an operculum. Miiller gave full particulars of this 

 curious instrument ; but he left it to posterity to inquire 

 its use. Strange to say, this great zoologist seems to 

 have imagined that the shell of this species (which he 

 calls Bulla Candida) belonged to some other mollusk, 

 which had served as food for his Lobaria ! The spire is 

 visible in Baltic specimens, and consists of between two 

 and three whorls ; this is clearly shown in the admiral^le 

 illustrations which accompany the first volume of the 

 work of ]Meyer and Mobius on the fauna of Kiel Bay. 



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