Handbook of Paleontology 145 



and smaller living species often are found in their 

 tangled masses. The sertularians are found everywhere 

 along the coast and are among the most common objects 

 found along the beach. Jellyfishes, which are part of the 

 plankton of the shore waters, are found cast up on the 

 beach, among them large forms such as the Milky-Disk 

 Jellyfish (Aurelia flavidula), the Speckled Jellyfish 

 (Dactylometra quinquecirra) and the Milky Cross (Stau- 

 rophora laciniata). The- Milky-Disk Jellyfish is 8 to 10 

 inches in diameter and may be recognized by the four 

 horseshoe-shaped reproductive organs near the center 

 which are yellowish white or pink in color. It is common 

 north of Cape Cod to the Arctic ocean, but is not very 

 abundant along the New York coast. The young are 

 found fastened on the rocks and seaweeds of the shore. 

 The Speckled Jellyfish occurs in the upper reaches of 

 bays and estuaries, from Florida to Cape Cod and in 

 some places is very abundant. It is a large form, reach- 

 ing a foot and a half in diameter. The Milky Cross 

 measures four to eight inches in diameter. It is very 

 abundant along the New England coast north of Cape 

 Cod, but in the spring may be found along the New York 

 shores. The effect of the cross is produced by the mouth 

 which is bordered by veillike frills. There is a small 

 form that looks like a large thimble of jellylike sub- 

 stance, the Thimble Jelly (Melicertum campanula) . This 

 is an arctic form which is extremely abundant north of 

 Cape Cod until the middle of summer, but is found far- 

 ther south only in spring. One of the most striking forms 

 that is frequently found stranded on the beach is the Sun 

 Jelly or Sea Blubber (Cyanea arctica). This is the larg- 

 est known jellyfish. The disk is amber colored, usually 

 three to five feet in diameter but one specimen was found 



