Whelks and Cone lets 257 



Sf 



protecting operculum, by the powerful dio-estivc fluid 



of the Star. Tlie 3^ellow egg-capsules of the Purple 



are very common objects on rock-ledges; 



each one contains from 20 to 40 embryos. 



M. Cailliaud declared not only that these 



are hatched by the parent, but that the 



father and the mother take turns to pro- ofM^rprrp" 



tect and incubate them. This, however, 



may be dismissed as " embroidery " not warranted by 



the observations of others, and in absolute opposition 



to all we know of the habits and customs of those 



mollusks that deposit eggs. 



The Dog-whelks (N'assd) are almost as well known 

 as the Purples, though their habits are different. The 

 animal may be distinguished from those of neighbour- 

 ing genera by the " tail " of the foot, which, instead of 

 ending in a blunt point, becomes divided and finishes 

 like a pair of tentacles, as shown in the figure of the 

 Netted Dog-whelk (N. reticulata). This species is 

 common on sandy shores all round our islands, 

 where it devours the bait on the 

 " spillers " of the flat-fisher and also 

 that in the lobster-pots. The animal 

 is got up to resemble the sand in its 

 colour and markings; the ground 

 colour is yellowish, over which is 

 thickly sprinkled dots of white and 

 various browns — a pepper-and-salt 

 mixture that assimilates closely to 

 the sand. When at rest, and on the 

 exposure of the shore by the receding tide, the shell 

 is half -buried in the sand. It is strongly ribbed in 

 two directions, so that a network pattern is produced 



