CHARACTERISTIC DEEP-SEA TYPES. ACALEPHS. 



131 



pointed conical bell, widening below into a funnel-shaped mar- 

 gin, the upper and lower parts of the bell being divided into 

 well-marked regions separated by a characteristic furrow. The 

 margin is formed by a number of gelatinous blocks closely fitted 

 together, which serve as supports for important organs caUed 

 socles. These support tentacles, marginal sense bodies, and thin 

 leaf-shaped lappets which have given the genus its name. The 



Fig. 425. Dodecabostrycha dubia. ^. 



stomach hangs down from the under side of the bell, and in its 

 spacious receptacles are found prominent filaments. The color is 

 blue. The American species P. hy-acintlnna (Fig. 426) extends 

 as far north as the coast of Greenland. 



None of these so-called deep-sea medusae, however, present 

 such remarkable features as the species of Atolla. The genus 

 has thus far been taken by the " Challenger " in the Antarctic 

 Ocean, on the borders of the South Atlantic and South Indian 



