REPORT ON THE HEXACTIXELLIDA. 403 



be folded. The thick wall of the cup thus folded consists simply of a system of anasto- 

 mosing tubes, which open internally into the gastral cavity, and probal)ly also directly to 

 the exterior. On the other hand, the connected interstitial system of spaces between the 

 above tube work is closed on the internal gastral surface of the body, but probably 

 covered externally only by a porous skin, which admits the incurrent water. 



Species 1. Dactylocalyx pumiceus, Stuchbury. 



The body forms a broad flat cup which is borne on a short, somewhat meshed and 

 thin- walled stalk firmly fixed to the substratum. The cup expands into a broad (30 cm.) 

 thin-walled plate- or cup-shaped body, which is laterally provided with a somewhat back- 

 ward bent, gently sinuous, rounded margin. The radially disposed grooves of the 

 external inferior and internal superior surface here and there exhibit a dichotomous 

 external division. The tubular network is very narrow meshed and the whole thick 

 connected skeleton is firm and strong. It is composed of finely-tuliercled beams without 

 thickened nodes of intersection. The loose spicules of the parenchyma are represented 

 by small hexacts with lank, terminally thickened, in part elongated and somewhat curved 

 rays, and also, according to Bowerbank,' by oxyhexasters with three long, slightly curved 

 terminals on each of the short principals, and lastly by discohexasters with somewhat 

 long terminals. The oxypentacts described by Sollas are to be referred to the dermal 

 skeleton. There is no trace of uncinates or of scopulse. Barbados ; West Indies. 



Species 2. Dactylocalyx s2ibglohosus, Graj'. 



A deep, thick-walled goblet in which the grooves on the gastral or internal surface 

 are less broad than those on the external. The parenchyma contains, besides hexacts 

 with terminal knob-like thickenings (sph^rohexacts) numerous discohexasters of various 

 size, with long terminal rays, but no oxyhexasters. The tangential rays of the rough 

 dermal pentacts are terminally club-shaped, while the longer proximal radial ray runs 

 out to a point. West Indies. 



Species 3. Dactylocalyx 2)cUella, n. sp. 



The dictyonal framework of this probably flat patelliform species, of which only a 

 fragment of macerated skeleton was procured, consists of smooth beams forming an 

 approximately square-meshed network, and forms an anastomosing system of tubes 

 which in many respects resemble those of the other species of Dactylocalyx, but are at 

 least twice as broad. (Perhaps identical with loanella compressa, 0. Schmidt, loc cit.) 

 Bermuda, 1075 fathoms ; coast of Portugal. 



' Pnc. Zool. Soc. Lonil, 1869, p. 7", pt. iii. 



