The Whelks. Trumpet Shells 



muscular double siphon. One tube admits water to the gill cham- 

 ber, the other discharges wastes. When the mollusk is in motion 

 the siphon is extended beyond the end of the shell and upward. 

 Under it the head protrudes, bearing the proboscis in front, and the 

 waving tentacles, each with a little black eye on the side. The foot 

 spreads broadly below the shell opening; the operculum lies flat 

 on the posterior lobe. The shell is carried in a horizontal position, 

 its spire directly above the operculum, its stem thrust forward. 



Few observers have ever seen the giant whelk lay her eggs, 

 though all know the long "egg ribbon" from which little whelks 

 emerge in the perfect image of their parents. It is known that 

 the process of egg laying is an exhausting one and takes con- 

 siderable time and energy. The first of the parchment-like sub- 

 stance is extruded upon a pebble or shell fragment which is chosen 

 as an anchor for the completed chain. The first few capsules are 

 small and far apart on the string. Then begin the perfect egg 

 cases, two keeled, and set close together. The string twists 

 spirally and is often a yard long, with nearly one hundred cases. 



Fresh ribbons are found during all the warm months along 

 the Atlantic coast. In each case the development of the egg 

 progresses, until the embryo stage is past. Then a round door 

 opens on the lower floor of the chamber, on the side opposite the 

 connecting string. Out tumble the little whelks and begin the 

 life of independence on the sea bottom. 



The Left-handed Whelk or Lightning Shell (F. per- 

 versa, Linn.) is much like the northern species, but the spiral turns 

 to the left instead of following the snail fashion. The young shells 

 are bright with zigzag brown lightning streaks that radiate from 

 the spire, crossing the fine spiral ridges that decorate the whorls. 

 The lip is lined with brown. The knobs are blunt. The body 

 is black. The shells fade and whiten with age; the largest speci- 

 mens are a foot long. They live on sandy beaches, and spend 

 much time burrowing just under the surface for bivalves. They 

 are preyed upon by Melongena. 

 Habitat. — Florida. 



Sub-genus SYCOTYPUS, Gill 



Shell with deep channelled suture, square-shouldered whorls, 

 without knobs; hairy, thick, brown epidermis covers exterior; 

 interior yellowish, smooth. 



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