BULLA. 4:37 



Bulla was also used by Rumph, previously to Klein, 

 but not in a generic sense. De Montfort cites 32 ver- 

 nacular names by which the shell was known in different 

 countries ; he called the genus Bullus. Leach proposed 

 Haminaa or Haminea and Romania for our two indige- 

 nous species ; the first of these names was given in Tur- 

 ton's tract on conchology. 



A. Thin ; crown imperforate, and spire wholly concealed. 

 1. Bulla hy'datis*, Linne. 



B. hydatis, Linn. S. N. p. 1183; F. & H. iii. p. 530, pi. cxiv. d. f. 7, and 

 (animal) pi. UU. f. 3. 



Body gelatinous, when fully extended and in motion of an 

 elongated oval shape and nearly as long again as the shell ; 

 colour variable, usually a mixture of purplish-brown, cinereous, 

 and orange-yellow, disposed in minute granular or confluent 

 specks : head large, notched in front : tentacles united, so as to 

 form a small squarish lobe or disk, somewhat narrower and 

 indented behind: eyes very distinct, placed far back on the 

 tentacular disk, and not very close together [" closely set," F, 

 & H.] ; they are black, and each lies in the centre of a minute 

 circular lucid spot : foot sinuous, capable of being considerably 

 dilated and extended ; the side-lobes are often reflected over 

 the greater part of the shell : gizzard encircled by a cartila- 

 ginous or muscular ring, with the alimentary canal issuing 

 from its centre ; plates dark purplish-brown or chocolate, 

 somewhat resembling the shells of a Chiton. (Montagu and 

 Clark). 



Shell roundish- oval, fragile, semitransparent and glossy : 

 sculpture, extremely numerous, delicate, spiral striae, besides 

 lines of growth ; the striae are scarcely perceptible unless with 

 microscopic aid: epidermis yellowish-brown, thicker than is 

 usually the case in this family : colour greenish-yellow, with 

 the crown and pillar white : spire concealed ; the crown or 

 apex is obliquely indented or slightly umbilicate : mouth irre- 

 gularly elliptical, rather narrow (although not much contracted) 

 above, and pear-shaped below ; total length exceeding that of 



* A water-coloured gem. 



