EE — OS —— 
REPORT ON CORALS—HYDROCORALLIN-#. . 61 
order to display the connections of the deeper reticulation with the dactylozooid and its 
general arrangement. The connections of the reticulations with one another are well 
seen at the cut edges of the bisected zooid systems, as shown in the plate. 
A tortuous and complicated mass of large canals springs from the bases of the 
gastrozooids at their margins, but not from their under surfaces. Some of these large 
canals turn also immediately after springing from the gastrozooids upwards, through 
the wall of the zooid system, to join the main network already described as communi- 
cating with the dactylozooids. The remainder of the large canals form a tortuous 
reticulation which passes down through the ecenenchym of the ccenosteum, by the side of 
the immediately adjoining zooid system, to anastomose with the corresponding reticula- 
tion arising from the base of the gastrozooid of this latter. _ The walls of the ampulle, 
as shown in the figure, are traversed by a fine reticulation of the ccenosarcal canals 
beneath their covering derived from the superficial layer of ectoderm. 
Nematophores, composed of nematocysts of the usual larger form, are placed on the 
pseudosepta, between the dactylozooids (Pl. VII. NN). 
Zooids.—One form of dactylozooid and one of gastrozooid only are present. 
Dactylozooids.—These, in the retracted condition, are short cylindrical bodies, with 
a rounded, blunt-conical, free extremity. They widen out towards their attached 
extremities, and are united to the sides of the dactylopores which are outermost in the 
systems, and to their styles, by elongate bases, which are drawn cut below into narrow 
prolongations which join the ccenosarcal meshwork. The zooids are, in fact, attached in 
an almost precisely similar manner to that in which the dactylozooids of Spintpora 
echinata are fixed within their groove-like pores. The free cylindrical portions of the 
dactylozooids in the present species are bent upwards, so as to extend in the wide upper 
cavity of the dactylopore in a direction parallel to that of the axis of the gastropore. 
They are seen thus projecting in the centrally placed zooid system represented on Plate 
VIL. D Z, showing partly free above the inner margin of the dactylopore sac, partly seen 
tbrovgh the transparent sac of the gastrozooid. A curved line, crossing them trans- 
versely, marks the point where the sac of the gastrozooid becomes bent over and unites 
with that of the dactylozooid. The dactylozooidsurfaces, as well as those of the tentacles 
of the gastrozooids, are thickly set with nematocysts of the usual smaller form. 
Gastrozooids.—These are short and broad cylindrical bodies somewhat contracted in 
diameter towards the middle of their length. They terminate above in a dome-like 
hypostome with the mouth opening at its apex, and are provided with a single whorl 
of light tentacles set on immediately below the hypostome. The tentacles are, in the 
contracted condition, very short and stout, with swollen, rounded, knob-like extremities, 
which reach to a height only just exceeding that of the summit of the hypostome. At 
the margins of their bases the gastrozooids (Pl. VII. G G) are drawn out into a series of 
large radially-disposed canals which lead directly into the cavities of the zooids, and 
