442 PATELLIDiE. 



exhibit no traces of eye-spots. The mantle has its edge 

 quite plain. The sides of the foot are not very steep, and 

 the disk of that organ is oval. The branchial plume is 

 not exserted when the animal is in motion. The tongue 

 when moderately magnified presents the appearance repre- 

 sented in our figure (Plate A A, fig. 3, b) as if it were 

 composed of a series of square divisions, each with a 

 bright yellow space in the centre, in front of which is a 

 strong curved brown tooth flanked by two brown denticles, 

 and bordered by uncoloured hooked teeth. A higher 

 magnifying power shows that the uncoloured lateral teeth 

 are accessorial (uncini of Loven). The teeth of the Nor- 

 wegian ally, the Patella cceca of M tiller, present a similar 

 arrangement according to Loven, but exhibit important 

 distinctions in detail. 



This mollusk was first announced as a member of the 

 British Fauna by Mr. Smith, of Jordan Hill, who dredged 

 it in the Clyde, off Arran. We believe it had previously 

 been found (though not published) by Miss M. Ball 

 adhering to a stone dredged from deep water on the 

 coast of Ireland. It has since been taken on the west 

 coast in fifty and sixty fathoms water off Cape Clear and 

 Mizen Head (M'Andrew). Adhering to a Pinna taken 

 on the coast of Cork (J. D. Humphreys). It is not rare 

 in the Clyde district, the Hebrides, and off the Zetland 

 Isles, where it occurs in depths of water between twenty 

 and eighty fathoms (M' Andrew and E. F). In thirty 

 fathoms twenty miles north of Kennard's Head, Aberdeen- 

 shire (Thomas). It inhabits the Norwegian seas, and is 

 found fossil in the coralline crag. 



