JETSAM 351 



and devoured its body, leaving the empty shell to be 

 tossed up on the sand. 



There are many curious items in the molluscan jetsam. 

 These chaffy balls that the wind blows along the sand 

 are the empty egg-capsules of the giant whelk or " roaring 

 buckie " cradles which were the scene of a grim struggle 

 for existence between the first hatched larvae and those 

 that emerge later. These translucent " sea-pens " of 

 chitin and these " sepiostaires " of spongy lime which are 

 collected for cage-birds to peck at, are both the vestiges 

 of the vanished shells of squid and sepia. Sometimes a 

 whole fleet of cuttle-fishes gets into the grip of the tide and 

 is stranded on the flat beach, where they writhe their arms 

 impotently till the gulls give them their release. 



Backboned animals do not contribute much to the 

 jetsam, but here and there we find a stranded fish, a bird 

 that has been killed, or a porpoise that has run aground. 

 Not very uncommon in some places is the body of an angler 

 or fishing-frog. This interesting fish often half buries 

 itself in the sand in relatively shallow water, and the lure 

 that dangles from the end of a long dorsal fin-ray seems 

 to attract little fishes to their destruction. A fresh speci- 

 men that has come too near the shore will afford an un- 

 forgettable instance of adaptation, for the numerous teeth 

 on the jaws that border the enormous gape are hinged at 

 their base, bending inwards at the least touch, so that 

 entrance to the mouth is as easy as exit is difficult. 



A distinctive " common object of the seashore " is the 

 four-cornered " mermaid's purse/' with each corner drawn 

 out into a tendril. It is the egg-case of a skate or of a dog- 

 fish ; it is made of keratin or horn, just as our finger-nails 

 are ; its tendrils twine automatically around seaweed, so 

 that the laid egg is saved from being smothered in the mud, 

 and is rocked by the waves till the embryo is ready to be 



