UNIVALVES. PATELLA. 107 



it is, from its similarity of shape, called the Fool's-cap. The 

 outside is usually of a pale fawn color, and the outer mar- 

 gin is bordered with a fine bristly epidermis; when the 

 interior is of a very bright pink color, it renders this 

 Limpet more valuable. 



The Patella Lutea is something like an Haliotis. The 

 Patella Pectunculus is covered with spines, and the Pa- 

 tella Perversa is remarkable for having its crown recurved, 

 and turned towards the hind part of the animal. There 

 are many Limpets which are very entire, and are not 

 pointed at the tip or crown. 



Amongst those most worthy of notice are the Patella 

 Afra, Patella Lusitanica, Patella Areolata, Patella Flam- 

 mea. Patella Indica, Patella Sanguinolenta or Bleeding 

 Limpet, and Patella Testudinaria or Tortoise-shell Lim- 

 pet; the latter is rather a rare species, and generally has 

 its interior of a silvery hue. The Patella Compressa is 

 remarkable for its narrow and lengthened form, which 

 gives it the appearance of having beeh squeezed or 

 pinched. 



The last division of the Patellae includes those which 

 have their tip or crown perforated : the principal species 

 rre the Patella Fissura, Patella Graeca, Patella Nimbosa, 

 Patella Jamaicensis, Patella Caffra, Patella Perforata, and 

 Patella Personata or the Radiated-mask Limpet, which, 

 when in fine preservation, is considered a rarity; it 

 grows to a considerable size, and is from the Falkland 

 Isles, and the Straits of Magellan. 



The Patella Mytiliformis very much resembles a My- 

 tilus or Muscle; it is from Ferroe Island. The Patella 

 Lacustris and Patella Fluviatilis, may be ranked among 

 the fresh-water species. 



The Patella Hungarica is sometimes found in a fossil 



