ECHINODERMATA OF NEW ENGLAND. 41 



B. II. 



Liriope. Body mushroom-shaped with flexible walls. 

 Tentacles long, flexible, four in number. Four radial tubes. 

 Proboscis pedunculated. Otocysts naked, with accompa- 

 nying tentacular appendages. Ovaries on radial tubes, 

 heart-shaped, slightly pendent from the inner walls of the 

 bell. 



L. scutigera. 

 Free-swimming larvae. 



The larval forms of the Trachymedusse are very rare in 

 Narragansett Bay. The youngest Trachynema which was 

 found has a disk-shaped body, very obscure proboscis and 

 eight tentacles alternating with eight otocysts. The sur- 

 face of the body and the tentacles are ciliated. 



O. discoides is a very rare medusa in New England wa- 

 ters and only two forms have been found ; one with eleven 

 and the other with fourteen tentacles. 



Order III. Siphonophora. 



Polymorphic medusae generally with a tubular-formed 

 body. With or without a float. With flask-shaped stomachs 

 (polypites), from which depend long, contractile tentacles. 

 Many have swimming-bells (nectocalyces) , covering-scales 

 and characteristic flask-like bodies called tasters. Colo- 

 nies monoecious or dioecious. Reproduction by ova and by 

 budding. 



A. With a float Physophoras. 



I. With an axis Agalmoides. 



Nanornia. 



II. Without an axis .... Physalia. 



B. Without a float Calycophorae. 



A. I. 



Agalmoides. Body tubular, with colored axis, size of 



