EGHINODERMA TA —PE DWELL ARLi<J 



:39r> 



pedicellarife are further attached by a strong elastic fibrous band to 

 this same plate. 



//. Stalked pedieellarise (Fig. 342, H, K).— Each pedicellaria 

 rises from a short, soft stalk ; the blades, of which there may be two 



Fig. 342.— Pedicellariae of Asteroids. A, B, C, D, E, F, P.seudo- <ir commencing pedicellaria of 

 various species. G, Sessile pedicellaria from the edge of the ambnlacral furrow of Gymnasteria 

 cariiiifcra (after Cuenot). H, Stalked straight pedicellaria diagrammatised (after Cudnot). J, 

 Basal portion of a stalked crossed pedicellaria of Astemcanthion ritbens (after Perrler). K, A 

 similar yediceUaria of Astcnicanthion (/tadnZis (after Cuenot). 1, Calcareous blade of the forceps ; 

 2, basal piece ; 3, occlusor muscle ; 3i, axial muscles of the blades ; 4, opening muscle ; 5, axial 

 band ; 6, epithelium ; 7, body wall ; S, stem. 



or three, articulate with a basal skeletal piece. The double-bladed 

 (didaetyle) pedicellariae are either straight (fopfleiform) or crossed 

 (foreipiform). Both kinds may be found in one and the same 

 animal. 



We select for description Asferias (glacialis), one of the Asteroids 

 most richly provided with pedieellarise, whose arrangement is specially 

 interesting. 



A. glacialis has three kinds of pedieellarise, straight, crossed, and 

 three-bladed. 



The crossed j^edicellarite are found in very great numbers, thickly crowded 

 together on a soft cushion, which surrounds the base of the spines, and into which the 

 latter can be withdrawn (Fig. 344). 



