MALACOZOA. GASTEROPODA. 345 



liform appendages ; mantle very large, widely open in 

 front, and also communicating by a fissure with a cor- 

 responding aperture in the apex of the shell ; two large 

 equal, pectinated branchiae ; intestinal aperture at the 

 extremity of a small tube opening into the respiratory 

 cavity. 



Shell oblong, conical, destitute of spire, having the 

 base oblong, with the margin continuous, the summit 

 truncate and perforated by an oblong aperture. 



1. Fissurella Nubecula. Red-rayed Fissurella. 



Shell oblong, conical, little elevated, with about fif- 

 teen broad ribs, alternating with smaller, and somewhat 

 reticulated with inconspicuous concentric lines ; the 

 colour brownish-red rayed with reddish-white. 



Shell ovato-oblong, somewhat translucent ; with the sides 

 of the aperture or base nearly straight, its margin plain, the 

 posterior extremity narrower ; conical, little elevated, with 

 the apex a little behind the centre, obliquely truncate, with 

 an elliptical aperture, having the margin smooth ; the exte- 

 rior rayed with alternate dark brownish-red and white bands, 

 and raised into fifteen thick ribs, with smaller intervening 

 ridges, and concentric elevated lines, decussating the rays, but 

 not very conspicuous ; the interior smooth, purplish-white, 

 and with a ring of pale-reddish purple around the thick 

 whitish marginal rim. Length three-twelfths and a-half, 

 breadth a little less than two-twelfths, height a twelfth and 

 a-fourth. 



The above description from an individual found by Mr. 

 Alex. Beaton, in February, 1843, adhering to an Actinia 

 from off Aberdeen. 



" Patella Nubecula. Lister. Conch. PI. 59." — Patella Nube- 

 cula. Turt. Conch. Diet. 142. — Fissurella Nubecula. Risso. Eur. 

 Merid. iv. 257. 



Natica monilifera. P. 51, 125. 



A great number of fine specimens of this animal 

 having been cast alive on the beach near Aberdeen, in 



