MR. H. N. MOSELEY ON THE STRUCTURE OF THE STYLASTERID2E. 475 
curved. Surface of the corallum smooth and nearly even. Pores of both kinds with 
simple circular mouths, irregularly scattered. Gastropores larger, less numerous, with 
a deeply seated brush-like style, and very thin and delicate tabulae placed at irre- 
gular intervals. Dactylopores devoid of a style. Ampullae, in male stocks, ovoid, 
entirely immersed beneath the surface of the corallum. Pores and ampullae more 
abundant on one face of the flabellum than on the other. Gastrozooids cylindrical, with 
four club-shaped tentacles, dividing at their bases into four main canals. Dactylo- 
zooids of various sizes, retracted entirely within the pores when at rest. Gonophores, 
in male stocks, ovoid, with a club-shaped spadix ; one, two, or three present in each 
gonangium, attached directly to offsets of the ccenosarcal canals. Female stocks 
unknown. 
Genus 2. Pliobothrus, Pourtales. — Corallum branching, with a tendency to form 
a flabellum. Surface smooth, marked with small linear openings arranged in rows, 
which in the recent state contain branches of the superficial ccenosarcal meshwork. 
Inner parts of the corallum very coarsely porous. Pores irregularly scattered. Gas- 
tropores circular-mouthed, their cavity tubular above, but expanding below into a 
basin-shaped chamber, without a style, often with one or two tabulae. Dactylopores 
showing as minute openings at the tips of small tubular projections, devoid of styles. 
Ampullae rounded cavities ; in the female very large, in the male smaller ; placed deeply, 
often in the axis of the corallum. Gastrozooids flask-shaped, devoid of tentacles, 
communicating with the coenosarcal meshwork by numerous offsets arising all around 
their bases. Dactylozooids entirely retracted when at rest. In the female a single 
gonopliore in each gonangium ; in the male, a group of gonophores (?) in each 
ampulla. 
Genus 3. Errina, Gray. — Corrallum branching with a tendency to form an irre- 
gular flabellate expansion. Pores most abundant at the tips of the branches ; irre- 
gularly scattered. Dactylopores with delicate nariform or scale-like projections, which 
vary much in form, being sometimes drawn out into tubes opening on one side by a 
slit as the pore mouth, but often coalescing, so that two or three projections have a 
common base and form large scales perforated by the pores ; devoid of styles ; scales 
all with a tendency to incline towards the tips of the branches. Gastropores with 
irregularly circular mouths, often seated in depressions ; with a deeply seated style. 
The mouths of the gastropores frequently covered by the dactylopore projections 
inclined more or less over them. Sometimes the margin of the gastropore itself is 
raised up on one side into a scale inclined over the pore mouth, but this is usually fused 
with neighbouring dactylopore projections. Ampullae on both sides of the flabellum ; 
prominent in the female. Gastrozooids cylindrical, with four club-shaped tentacles and 
four basal canals. Dactylozooids entirely retracted. Gonophores in the female solitary 
in the gonangia. The free margin of the cup-shaped spadix becomes converted into 
a ramified fringe, embracing the embryo as development proceeds. Planula as in 
Pliobothrus, Structure of male stocks unknown. 
