The Whelks. Trumpet Shells 



C. cancellaria, Qmr., is ash-coloured, has strong spiral ribs, 

 crossed by longitudinal folds, forming fine tubercles. Lip strongly 

 lined within; spire prolonged; canal recurved. Length, i to i^ 

 inches. 



Hahitat. — Gulf of Mexico. 



THE TYPICAL WHELKS 

 Genus BUCCINUM, Linn. 



Shell oval or oblong; spire elevated, acute; epidermis horny; 

 colour dull ashen; aperture oval, large; canal wide, short; 

 columella expanded, smooth; outer lip thin, smooth inside; 

 operculum ovate, nucleus sub-marginal, small ; radula prominent. 



A carnivorous genus of few species, in northern waters. 



The Waved Whelk (5. undatum, Linn.) is a circumpolar 

 species which extends its range southward as far as New Jersey 

 and the JVlediterranean, varying from the type so far on American 

 coasts as to induce some scientists to accept the name, B. undu- 

 latum of Miiller. It has a steep spire of rounded coils, ridged with 

 fine grooves and made wavy by crossing a dozen or more longi- 

 tudinal folds that fade out at the middle of the body whorl. The 

 animal is aggressively carnivorous, and has demonstrated its, 

 ability to adapt itself to varying circumstances. 



It is not surprising to find in such a mollusk that the osphra- 

 dium, or organ of smell, is very large. It lies like a plume-shaped 

 gland in the wall of the mantle cavity close to the gill. One might 

 easily mistake it for a secondary breathing organ. The third and 

 largest in the series of curved and flattened organs on the left side 

 of the body is the gland that secretes quantities of glary mucus. 



The egg cases of this whelk are attached, and the mass looks 

 like a coarse sponge when picked up on the. beach. Sailors use 

 them as a soap substitute under the name of "sea wash balls." 

 Each capsule is a tough pouch like a large split pea, attached by 

 its side. Several hundred eggs occupy each cell, and there are 

 five hundred or more capsules in an average mass. As they 

 hatch, the vigorous embryos devour the weak ones, so the numbers 

 are greatly reduced. The development occurs in winter and re- 

 quires about two months before the fry are ready to leave the 

 egg capsule. 



