SHELLS WITHOUT A REGULAR SPIRE. 51 



Ilaliotis tuherculata—Tim Tubercular Haliotis. Plate IX. 

 fig. 31. Dull reddish brown on the outside, sometimes clouded 

 or mottled with a deeper shade : longitudinally striated, and trans- 

 versely wrinkled, with a few raised tubercles ; inside pearlaceous, 

 reflecting the most beautiful shades of pink, blue, green and yel- 

 low ; aperture open the whole length of the shell, outer lip irreg- 

 ular; from three to four inches long. Inhabits the sea at 

 Guernsey. 



It is asserted, that as a new hole is added by the animal to the shell, it 

 carefully closes up the next open one to the spire ; by which means the num- 

 ber of orifices is, in general, the same in all shells of one species. 



DIVISION SECOND.— SHELLS WITHOUT A REGULAR SPIRE. 



Genus .32.— PATELLA. 



Animal a Limax ; shell univalve, subconic, shaped like a 

 bason ; without a spire. 



Linne divides this g-enus into five families : * furnished with an internal 

 lip; shell entire; **with the margin angular or irregularly toothed; 

 *** with a pointed recurved tip or crown ; **** very entire, and not pointed 

 at the tip or vertex; ***** with the crown perforated. 



Patella vulgata. — The Common Patella. Plate IX. fig. 

 .32. Subject to great external variety ; ribbed from the vertex 

 to the margin in some specimens, and with divergent strife ; 

 others are striated merely without ribs ; of a dark brown or 

 olive green on the outside, and, the inside blue shining with 

 deep purple radiations ; and subject to great variety of colour ; 

 apex obtuse and placed towards the narrow end of the shell, 

 which is usually ovate. From one to two inches long. Inhabits 

 the shores of Northern Europe. 



Patella Chinensis. — The Chinese Patella. Plate III. fig. 

 6. (Calyptra^a sinense, Lamarck.) Shell sub-conic, sub- 

 pellucid, and very thin, colour whitish, much compressed, round- 

 ed at the margin ; vertex central, terminating in a sub- spiral 

 volution, with usually a number of concave scales. Inside while, 

 glossy, and smooth, with a sub-spiral columella or pillar-lip, ex- 

 tending from nearly the margin to the end, and forming the ex- 

 ternal sub-volution ; it is broad, flat and oblique. Found in 

 Helford harbour, Cornwall ; in Salcomb bay, Devonshire, by 

 Mr Montagu ; and near Dunbar, by Captain Laskey. 

 e2 



