MONOGRAPH OF THE EXISTING CRINOIDS. 



231 



Family COMASTERID^. 



Vomutella nigra. — Excepting for a superficial layer of very numerous and 

 very minute spicules no calcareous deposits could be detected in the thick ventral 

 perisome. 



No calcareous bodies were found in the tentacles. 



Comatella stelligera. — The conditions are the same as in the preceding species. 



Comatella maeulata. — The conditions are the same as in the two preceding 

 species. 



Neocomatella jmlchelU (figs. 782, p. 366, and 792, p. 372).— Toward the distal 

 end of the outer pinnules where they are most developed the calcareous deposits in 

 the perisome of the pinnules are in the form of very thin and delicate calcareous 

 films, one to each of the ambulacral lappets, very irregular in outline and con- 

 siderably elongated at right angles to the pinnulars. The deposits usually, 

 however, consist of a series of very slender and irregular forked or branched 

 rods, in general lying at right angles to the edge of the pinnulars, intermingled 

 with spicules, forming a layer of irregular spicules and rods. In the proximal 

 two-thirds of the pinnules this layer is composed mainly of branched spicules 

 more or less evenly spaced and with no definite orientation, forming an inter- 

 rupted reticulation, but distally the spicules gradually give way to evenly spaced 

 rods, two or three to a pinnular and at right angles to their borders. 



Small spicules are present in the tentacles. 



Neocomatella alata. — Toward the distal end of the outer pinnules, where 

 they are most developed, the calcareous deposits are in the form of very thin 

 and delicate calcareous films, very irregular in shape, rather large, somewhat 

 longer at right angles to the pinnules than broad at the widest part. The deposits 

 are usually reduced to a series of slender, irregular, branched or forked rods inter- 

 mingled with spicules, forming an interrupted reticulation in the perisome of 

 the pinnule which in their distal third gradually transforms into a series of 

 more regular and evenly spaced rods at right angles to the pinnulars. 



The tentacles contain irregular spicules and occasionally long and very narrow 

 cribriform films. 



Capillaster sentosa. — Except for numerous minute superficial spicules the 

 ventral perisome of the arms and pinnules appears to be without calcareous 

 deposits. 



No spicules were detected in the tentacles. 



Capillaster muUiradiata. — Toward the ends of the distal pinnules the apices 

 of the ambulacral lappets contain small calcareous films which may be continued 

 downward toward the pinnulars in the form of very narrow extensions; the 

 lateral perisome of the pinnules contains more or less regularly spaced rods stand- 

 ing at right angles to the borders of the pinnulars. In most pinnules no calcareous 

 deposits could be found. 



There appear to be no spicules in the tentacles. 



Capillaster coccodistoma. — I was not able to find any calcareous deposits in 

 the brachial or pinnular perisome of this species. 



142140— 21— Bull. 82 17 



