The Purples. Dog Winkles 



vein or sac on the back of the body. Its use to its owner is the 

 same as the ink of the common squid. A jet of ink colours the 

 water, and enables the pursued to escape from an enemy. We 

 can understand how hard and tedious was the process of obtaining 

 this dye in quantities. 



The complex art of blending the juices to produce the desired 

 play of colouring was known only in ancient Tyre, and this secret 

 was lost when the city was destroyed. Meanwhile the cochineal 

 bug and modern coal tar dyes have supplied cheaper materials. 



"In the reign of Augustus one pound of wool dyed with 

 Tyrian purple sold for about ^36 sterling." Six pounds of liquor 

 were required to one pound of wool. Consequently fabrics when 

 dyed often cost their weight in gold. 



The Princely Purple (P. Persica, Linn.) is the type of this 

 genus. It is oval, with a short spire; its brown surface \s regu- 

 larly spirally grooved, and wound with a narrow band of white, 

 dotted with brown. A row of nodules encircles the upper whorls. 

 Columella reddish yellow; aperture wide, pinkish or bluish 

 within; lip thin, with five interrupted brown lines crossing the 

 inner margin. Length, 3 to 5 inches. 



Habitat. — Philippines. 



The Open-mouthed Purple (P. patula, Linn.) is like the 

 preceding in size, colour scheme, wide columella and gaping 

 aperture. The spire is depressed, however, and the spiral ridges 

 are much stronger, and irregularly tubercled. The lip is fluted, 

 and marked with the dark brown that alternates with white on 

 the outer surface. The columella is reddish chestnut, with a dark 

 brown semi-lunar patch at the top. The sculpture is much 

 sharper in young than in adult specimens. 



Habitat. — Gulf of California, Philippines, West Indies. 



The Chocolate Purple (P. chocolatum, Duclos), with deep 

 chocolate exterior, knobbed along the square shoulders, and 

 closely ridged on the thick lip, is described as a very active mol- 

 lusk. The early Peruvians must have used the mollusk as food, 

 judging by the piles of shells found near the tombs at Arica. 

 Length, 3^ inches. 



Habitat. — Peru. 



Another large species which Reeve calls P. giganiea, is con- 

 nected by intermediate forms with P. consul, Lam. Spire is sharp; 

 whorls encircled with fine brown lines; shoulders square, tuber- 



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