ANNULOIDA: ECHINOUERMATA. 1 57 



More recently a stalked Crinoid has been discovered in the 

 Atlantic and North Sea, and has been described under the 

 name of Rhizocrinus Lofotensis (fig. 44). The chief interest of 

 this form is the fact that it belongs to a group of the Crinoidea 

 hitherto believed to be exclusively confined to the Mesozoic 

 Rocks — viz., the Apiocrinida or " Pear-encrinites." In fact, 

 Rhizocrinus is very closely allied to the Cretaceous genus 

 Bourgueticrinits, and it may even be- doubted if it is generically 

 separable from it. The late remarkable researches into the life 

 of the deeper parts of the ocean have brought to light several 



Fig. 45. — Crinoidea. Comai^la rosacea, the Feather-star ; a Free adult ; 

 b Fixed young. (After Forbes.) 



new Crinoids, which will doubtless, when fully investigated, 

 still further fill up the interval between the living and extinct 

 Crinoidea. 



In the second type of the Crinoidea — represented in our seas 

 by the Coinatula (fig. 45), or Feather-star.— the animal is not 

 permanently fixed, but is only attached by a stalk when young 

 (fig. 45, b), in which condition it was described as a distinct 

 species, under the name of Pentacrinus Europmus. In its adult 

 condition, however, the Comatula is free, and consists of a pen- 

 tagonal disc, which gives origin to ten slender arms, which are 



