r o m sound to sea 



What /Ire Those Things, Anyway? 



An Egg off a 

 Different Kind 



Pretty shells aren't the only ocean 

 gifts you'll find at the tide line. Egg 

 cases of different sizes, shapes and ori- 

 gins commonly wash ashore along Tar 

 Heel beaches. 



A String of 

 Whelk Iggs 



Who would have thought that the 

 hard-shelled whelk would begin its life 

 in a necklace of eggs? 



The mother whelk secretes a spiral- 

 ing strand of parchmentlike oval sacs 

 filled with eggs. After creating these egg 

 cases, which can measure up to 2 feet 

 long, the mother whelk attaches them to 

 a shell or rock or buries one end in the 

 subtidal sand. Often, however, the cases 

 wash ashore after becoming dislodged 

 by storms and waves. 



Inside each sac are 20 to 100 eggs. 

 Baby whelks, about the size of the dot 

 over this "i," first hatch inside the sac, 

 where they feed on other unhatched 

 eggs and stored protein. After about two 

 weeks inside the sac, the baby whelks 



chew their way out of the incubation 

 chamber. 



Each whelk hatchling emerges as a 

 miniature version of its parents, with its 

 tiny shell having only one whorl. 



The egg sacs of different whelk spe- 

 cies vary in shape. The sac edges of the 

 knobbed whelk are flat and square; but 

 the edges of the channeled whelk are 

 sharp. 



Devils' Pocketbooks 



Coastal folks call them "devils' 

 pocketbooks" or "mermaids' purses." 

 Landlubbers often question the identity 

 of the hard, black pouches that wash up 

 along our state's beaches. 



They're the egg sacs of skates, those 

 fan-shaped marine critters with the long 

 tail. The sacs are black, 1 to 3 inches long 

 and rectangular, with a curly horn at each 

 corner. The horns extract oyygen from 

 the water and extrude wastes. 



Inside each black sac is a single egg 

 with a large yolk. Female skates are mi- 

 grating inshore now to lay these eggs. 



The underside of the sac is sticky 

 and adheres to underwater plants. Hidden 



among the flora and protected by its 

 leathery encasement, the embryonic skate 

 develops, hatching three to 1 5 months 

 later. 



Each skate emerges as a miniature 

 adult, ready to fend and feed for itself. 

 Later, the egg sacs dislodge from their 

 plant hosts and wash ashore. 



Sand Collars 



Looking like a detachable collar or 

 the rubber cup at the end of a plumber's 

 helper, the egg case of the moon snail has 

 piqued the curiosity of more than one 

 summer beach vacationer. These gray, 

 rubbery collars are frequently found 

 among the beach wrack of seashells, sea- 

 weed and organic debris. 



Mother moon snails extrude their 

 eggs in a jelly like sheet that is held to- 

 gether with mucus and sand. The collar 

 shape is created as the eggy sheet wraps 

 around the muscular foot of the mother 

 moon snail. 



By August, the egg case will dry, 

 crumble and release about a half million 

 young hatchlings to the ocean. 



Kathy Hart 



COASTWATCH 21 



