5 



ECHINODERMS. 



heads have been regarded as petrified flowers, and designated 

 " Lily Stones " (Fig. 43, a). The origin of these beautiful fossils, 

 formerly so mysterious, is thus easily explained. 



The Feather-star (Comatula)* (Fig. 44, e), common upon our coast, is 

 but an Encrinite without a stem, and thus enabled to move freely at the 

 bottom of the sea. The central box which contains the stomach is furnished 

 with a mouth, around which radiate the arms, fringed with a double row of 

 jointed filaments ; by means of these the feather-star can creep upon the sand, 

 or twining them around the stems of sea- weeds or corals, it can climb in search 

 of food, or by the undulations of its feathery filaments, row itself from place 

 to place through the water, with a graceful gliding motion. 



FlG. 44. ECHINODERMATA. 



The Sea-baskets (Gorgonocephalus}\ (Fig. 44, 5). In these elaborately 

 constructed creatures, the shell of the living animal is entirely covered with a 

 thick fleshy crust. From the circumference of the disk proceed fiv.e strong 

 rays, which, subdividing again and again, always by binary division, soon 

 become multiplied into living ropes, spread out all around the body; and 

 being made up of an immense number of jointed pieces, they are as flexible 

 as whip-cord, and as manageable as the legs of a spider. Each of these 

 innumerable cords is, in the living animal, terminated by a minute yellowish 

 fleshy ball, something resembling a little foot, so that the whole creature, as 

 it walks along, appears like a conglomeration of serpents, strangely linked 

 together, whence it has not inappropriately received its mythological name of 

 Gorgonocephalus, or Medusa's Head. These star-fishes inhabit the deep parts 



* Comatus, having hair, f Topyuv , Gorgon, Medusa; /ce0a\??, kephale, the head. 



