MR. H. N. MOSELEY ON THE STRUCTURE OE THE STYLASTERIDzE. 
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expanded. They have each a well-developed hypostome and six tentacles, 
and join the coenosarcal network at their lower extremities by means of 
four main canals. 
PLATE 39. 
Vertical section, throng'll one of the cyclo-systems of zooids of a male stock of 
Allopora profunda decalcified. Right and left of the centrally placed system seen in 
section, are represented parts of two other similar systems, which are shown as seen 
from their outer aspects by transmitted light, and not in section. 
D Z, D Z. Dactylozooids retracted. Arranged in a circlet around the mouth of the 
pore of the gastrozooid. 
P, P. Sacs, or soft tissue walls of the pores, of dactylozooids, separated from one 
another by pseudosepta. Two of these sacs are shown cut open to display 
the attachment of the bases of the zooids within them. 
G Z. Sac of the gastrozooid, between which and the place occupied in the recent 
condition by the wall of the pore of the zooid is a wide space, traversed 
by radially disposed offsets of the coenosarcal network, R R. 
X, X. Interradial spaces between these effects. 
Z. Gastrozooid with twelve tentacles, disposed in a single whorl, and an almost hemi- 
spherical hypostome. Large canals spring from the base of the zooid, and 
form communications with the basal canals of adjacent zooid cyclo-systems. 
D Z', D Z'. Dactylozooids in their sheaths seen from behind within the adjacent 
zooid cyclo-systems. 
G, G, G. Gonophores. The sac of one of these is cut open to show the ovoid male 
generative masses and then spadices lying within. 
PLATE 40. 
Shows the structure of Stylaster densicaulis as seen in the decalcified condition. 
The cylindrical masses formed by three cyclo-systems of zooids are shown cut open, so 
as to demonstrate the arrangements of the zooids and coenosarcal ramifications within 
them. The positions of the two additional cyclo-systems are indicated by outline. 
In the centrally placed cyclo-system the entire ra mi fications of the coenosarcal canals 
are shown. 
In the system displayed on the left side of the figure, the wall of the sac of the 
gastrozooid, and the superficial network beneath it, are removed, in order to show 
the connexions of the bases of the dactylozooids with the deeper canals. 
In the system shown on the right in the figure, the details of the connexion of the 
base of the gastrozooid with the coenosarcal canals only are given. 
The gonophores are seen through the superficial networks existing in the walls 
of the ampulla. 
