Objects for the Microscope. 161 



it backwards and forwards, but raising or depressing the 

 teeth. 



The whelk is largely consumed in London ; it is dredged 

 off every part of the British coast. Dr. Johnson tells us 

 that at the enthronisation feast of William Warrham, 

 archbishop of Canterbury, in 1504, 8,000 Whelks were 

 dressed as side dishes for the lordly epicures of those 

 days. 



PALATE OF PURPUREA. 



The Purpurea, or Dog-whelk, is a small species of Buc- 

 cinum very abundant on our rocks ; it has a white shell, 

 and is often found with a little semi-transparent flask beside 

 it, or a cluster of them filled with eggs, which are most in- 

 teresting microscopic objects, as the development of the 

 little mollusc is easily watched. The palate is pretty and 

 resembles that of the larger Buccinum. It was from this 

 shell-fish that the Tyrians procured their famous purple dye, 

 making a bath of the liquid in the proportion of two pounds 

 of Buccinum liquor to one pound of the purpurea. The 

 process being tedious, and the needful quantity of these 

 little creatures very great, the price of the wool so dyed 

 was enormously high no less than 1,000 Roman denarii, 

 or thirty-six pounds sterling, per pound. 



NASSA. 



A smaller species of Buccinum. 



PALATE OF TROCHUS ZIZIPHINUS. 



This is the palate of that very pretty variegated spiral 

 shell called " Tops," which we delight to find on the rocks 

 at low water under the thick hanging masses of sea-weed. 

 No palate is so beautiful, or requires such careful exami- 

 nation ; for when we have had a general view, we should 

 always use a higher power, and explore further the won- 

 derful workmanship displayed in this tiny tongue. Not 

 only are there triple rows of finely notched teeth arching 

 over towards the centre, but the intermediate space is 

 thronged with delicate leat-like teeth, curved downwards 



