492 
MR. H. N. MOSELEY ON THE STRUCTURE OF THE STYLASTERID2E. 
G Z. Moutl 1 of the sac of a gastrozooid, which sac is cut open in order to show the 
contained zooid. 
T. Tentacle of the zooid. O. Its mouth. 
C. Gastric cavity. St. Style. 
X, X. Spaces in the coenosarcal network, homologous with the inter-radial spaces in 
Sporadopora. 
Three gonophores are represented in the figure, showing three successive stages 
of development, the central one of the three being most advanced. 
O Y. Ovum. S. Spadix shown in section. 
In the central gonophore the planula which is shown in section is doubled up 
somewhat, being fully developed, and ready to escape. 
E C. Ectoderm of the planula. 
E. Endoderm. 
B. Membrane immediately covering the planula where not in contact with the spadix. 
A. Surface layer of endoderm reflected over the wall of the ampulla. 
In the remaining gonophore the developing planula and its spadix are shown entire, 
the surface membrane only covering the wall of the ampulla being seen in section. 
P. Planula. 
S'. Spadix showing the manner in which it forms a network and becomes digitate or 
fringed towards its outer margin. 
N, N, N. Nematophores. 
PLATE 38. 
Longitudinal section through the axis of a branch of a stock of Spinipora echinata, 
decalcified, showing the coenosarcal network and the surface membrane, with the 
various zooids in their mutual relations. 
I) Z, D Z, D Z. Indicate some of the larger dactylozooids, of which many are shown. 
These larger dactylozooids are situate near the extremities of spine-like 
processes of the corallum, represented here by the corresponding lamina; 
of soft tissue, extensions of the surface layer of ectoderm. The processes 
are grooved on the side lying towards the tips of the coral branches, for 
the reception of the zooids, which are all shown here as much contracted. 
A, A. Examples of the fusing of two adjacent processes. 
B, B. Processes represented as cut open in order to show the disposition of the bases 
of the dactylozooids within, and their connexion with the coenosarcal 
network. 
D, D. Small dactylozooids protruded from simple pores near the bases of the spine-like 
processes. 
G Z, G Z, G Z. Gastrozooids seen ; some retracted within their sacs, others partially 
