LITTORINA. 365 



at least two- thirds, and in the male not much more than one- 

 half of the spire : suture more or less deep, and always distinct : 

 mouth equal to about one-third of the lower portion of the 

 shell in females, but proportionally much smaller in males, 

 angulated and slightly channelled above, and considerably ex- 

 panded as well as angulated below: outer lip thin, a little 

 reflected, incurved towards the pillar : inner lip united with 

 the outer lip, and forming a thin glaze on the upper part of 

 the mouth : pillar short, but thick and very broad, especially 

 at the base ; it shelves inwards, and is white or light-coloured : 

 inside of a danker hue in coloured specimens : operculum horn- 

 colour, having four or five volutions, which are crossed by 

 curved and rather numerous striaa in the line of growth ; the 

 * under side has an irregular boss in the centre of the spire, 

 but no rim as in the last species. L. 0-65. B. 0'5. 



Var. 1. saxatilis. Stunted, nearly globular, usually smooth 

 or finely ribbed ; colour greyish with a white base. L. saxatilis, 

 Johnston, in Proc. Berw. Nat. Club, i. p. 268 ; F. & H. iii. p. 43, 

 pi. Ixxxvi. f. 4, 5. 



4 Var. 2. sukata. Bibs flattened; colour yellow, with pur- 



plish-brown furrows. Turbo sulcatus, Leach, Syn. Moll. G. B. 

 p. 187, tab. ix. f. 6. 



Var. 3. jugosa. ( Smaller than usual, having strong and 

 . _. sharp spiral ridges, which are variable in number, and some- 

 ' * times alternately larger and smaller. T. jugosus, Mont. Test. 

 Brit. pt. ii. p. 586, tab. xx. f. 2. 



Var. 4. patula. Ear-shaped and expanded, thinner ; spire 

 not prominent, placed somewhat obliquely ; mouth wide. L. 

 patula, Jeffreys (erroneously), Thorpe's Brit. Mar. Conch. 

 p. 259 ; F. & H. iii. p. 36, pi. Ixxxv. f. 6-10, and (animal) 

 pi. G G. f. 2. 



Var. 5. globosa. Larger, globular, thick, and nearly smooth. 



Jyt*. - 



Var. 6. tenebrosa. Smaller, thinner, smoother, more tur- 

 reted, and having a deeper suture, dusky and often tessellated 

 or chequered. T. tenebrosus, Mont. Test. Brit. pt. ii. p. 303, 

 tab. xx. f. 4. L. tenebrosa, F. & H. iii. p. 39, pi. Ixxxiv. f. 11, 

 12, and Ixxxv. f. 1-5. 



Var. 7. similis. { Resembling the last variety in size and 

 shape, but more distinctly ribbed. 



Var. 8. Icevis.. Oval, solid, and smooth. 



