258 Shell Life 



by the depressions, but the prominences are so nearly 

 equal in height that it does not present the bold 

 aspect of some allied species. The colour 

 is a dull buff tinged with brown, except 

 the inner and outer lips, which are white, 

 highly polished, the outer lip with 12 

 or 14 tooth-like elevations. The egg- 

 capsules in this case are flattened oval 

 pouches, attached by a short footstalk to 

 the fronds of the Grass-wrack {Zostera). 

 Full-sized specimens measure about 1\ 

 inch. 



The Thick-lipped Dog-whelk (iV^. incrassata) is 

 little more than half an inch long, entirely different 

 in appearance from the Netted species, the ridges 

 across the whorls being stronger than those having a 

 spiral direction, the colours being brighter, and the 

 outer lip being greatly swollen, white, with an almost 

 black spot in the canal. The colour varies from 

 white or flesh colour to a pale warm brown, the 

 whitish specimens being more or less striped or 

 mottled with brown. It is equally common with the 

 last species all round our islands, but affects stony 

 ground, at all depths between low water and 145 

 fathoms. The Dwarf Dog- whelk (JV. pygincaa) is a 

 less solid shell, the spiral ridges fewer and finer, 

 the colour always yellowish white tinged with 

 tawny, the outer lip even more swollen, white, but 

 brown within, and therefore showing no spot in 

 the canal. It does not attain the length of half an 

 inch, and it is much more restricted in its range. 

 It has been found in the coralline zone on the 

 coasts of Dorset, Devon, and Cornwall, also at 



