REPORT ON THE HEXACTINELLIDA. 379 



wall has become the external wall of the body, while the other internal portion of the 

 gastral wall, which exhibits the roundish excurrent apertures of the efferent canals, is 

 continued directly into the internal surface of the stalk lumen. The fine quadratic 

 lattice-work of the dermal membrane lies on the inferior surface of the body. The 

 parenchyma contains between long diacts numerous oxyhexasters, and, though less 

 abundantly, also discohexasters. The dermal and gastral membranes exhibit a pre- 

 dominant or exclusive occurrence of small rough pentacts. 



Species 1. Aulochone cylindrica, n. sp. 



The cylindrical body, about the size of a child's fist, exhibits a funnel-shaped gastral 

 cavity, and on the superior everted margin of the gastral membrane a somewhat sharp, 

 undulating edge, while the lower or true oscular margin is more uniformly sharp and 

 smooth. Among the numerous oxyhexasters of the parenchyma, much dwarfed forms 

 occur. The discohexasters have numerous terminal rays arranged in a tuft on each 

 principal. Between the rough pentacts of the dermal membrane there are sometimes 

 also similarly formed tetracts. The gastral membrane contains exclusively rough 

 pentacts. North-east of the Kermadec Islands, 600 fathoms. 



Species 2. Aulochone lilium, n. sp. 



The lateral surface of the hemispherical, rather than cylindrical body is some- 

 what puffed out, and passes not so much by a superior edge as by an arched marginal 

 region into the funnel-shaped wall of the gastral cavity, while towards the dermal 

 inferior surface it is very distinctly defined by a sharp-edged oscular margin. The 

 parenchyma contains, besides numerous oxyhexasters with long rays, also discohexasters 

 with S-shaped terminals arranged in calyx-like fashion. Both dermal and gastral 

 membranes contain rough pentacts. Meangis Islands, north-east of Celebes, 500 

 fathoms. 



Genus 9. Caulocalyx, n. gen. 



With the single species, Caulocalyx tener, n. sp. 



The simple cup-shaped body is gradually contracted inferiorly into a solid narrow stalk. 

 From the smooth lateral wall long isolated oxydiacts project radially. Between the long 

 diacts of the parenchyma discohexasters of variable strength project, in which the long 

 terminal rays are gradually thickened towards the outer end, and terminate in a margin- 

 ally toothed hemispherical transverse disc. The dermal skeleton contains oxypentacts 

 with spines on the four tangential rays. West of Tristan da Cuuha, 2025 ftithoms. 



