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, pp. 33, 34. There is comity which
Brit., pp. 33, 34), simply resting in the mud, without having the base attached to anything. There is a peculiarity in the colouring of many of the specimens found at this locality which we have not observed in those taken at other places. The peculiarity consists in the presence of a dark wedge-shaped mark on the disk, the point of the wedge touching one corner of the mouth, while the diverging lines which form the sides of the wedge run right out to the tentacles. Usually nine of the principal radii are enclosed in this dark-coloured mark, while the remaining fifteen are much more lightly coloured. This curious division of the disk into dark and light regions is found in varieties otherwise widely differing. It is sometimes somewhat accentuated by the gonidial tentacle at the pale-coloured end of the mouth being pure ivory white. Gosse's variety sordida is, as might be expected from the nature of the locality, very common at Malahide. The variety named versicolor is also represented, and many specimens which come within Gosse's description of it have conspicuous spots like the Greek letter Sigma on the twenty-four principal tentacles, there being two such spots on the six tentacles constituting the inmost row. A fair number of specimens found at Malahide have the principal radii of a paler hue than the rest of the disk, which is thus decorated by a stellate pattern. We do not think this variety is described elsewhere, but we were greatly interested in finding it, because we believe it must have formed the model from which the late Professor Harvey drew the two sketches to be found in his Sea-side Book, pp. 119, 120.
Sometimes the younger forms of this anemone prefer to remain unattached, and lie wallowing on the bottom of the tank with their bases so much distended as to resemble the dilated physa of the free or non-adherent actinians. We have observed this habit also in the case of Cylista viduata, adult specimens of which often behave in a similar manner.
The very special arrangement of the tentacles and mesenteries at the outer edge of the disk may be observed in transparent specimens of this species. We have not found the same arrangement in any other actinian, and it would seem to be as distinctively characteristic of Cereus pedunculatus as the over-hanging salver-shaped disk with the structure of which it is evidently intimately related. If we trace in the external body-wall of the columns the insertions of a pair of principal mesenteries, we shall be able to follow from the base upward the lines which mark them quite easily for at least twothirds of the column. But when we have traced them up to the point
where the column begins to expand outward we find that the two lines converge, and, meeting in a point, do not extend any higher up the external wall of the column. The lines marking the insertions of the secondary mesenteries present the same appearance; a little higher up the column than where those of the primary mesenteries converge and stop we find the insertions of the secondary mesenteries converge and stop too; and so with the tertiary mesenteries also. But though the lines of the insertions of the mesenteries do not mark the column after they have thus converged, it is quite easy to see the
esenteries themselves inside rising up to the disk where each pair is crowned with its corresponding tentacle. The mesenteries, however do not extend further from the mouth along the oral disk than the tentacle, and their outer edges, instead of being attached to the bodywall, hang free in the general cavity, until the body-wall, as it gradually contracts, comes under the base of the tentacle to which the mesenteries are attached. Here the mesenteries are attached to the body-wall of the column, and descend from thence to the base in the usual way. But it must not be supposed that the upper part of the column has, on this account, fewer lines of insertions appearing in it than the lower. For the contrary is the fact. Each of the outer tentacles has its own pair of mesenteries, and the insertions of these run down the column from the margin of the disk for a greater or less distance, those corresponding to the tentacles of the outermost row being the shortest. Immediately behind the last row of tentacles there may be seen with a low magnifying power a series of knobstwo between each pair of tentacles-forming the margin of the disk. These knobs are young tentacles.
We have observed the occasional prolongation of a single tentacle in this species. One very bright day in September we saw in nearly all the pools we examined several individuals having each one tentacle prolonged in the manner described by Gosse (Actin. Brit., p. 34). The elongated tentacle was moved in a circular manner, sweeping round the whole animal apparently in search of food. In some cases, but not in all, it was the tentacle at one of the corners of the mouth that was elongated. In one or two instances the elongated tentacle belonged to the second row. We cut off the light from the anemones, and the elongated tentacles were almost immediately withdrawn.
SAGARTIA MINIATA, S. ROSEA, S. VENUSTA, S. NIVEA. These anemones may be obtained at Dalkey Island. We have examined the extreme top of the column just under the tentacles in
specimens of all four species. They all present a precisely similar appearance, very different, however, from that exhibited by Cereus pedunculatus. When the animal is fully extended an observer, placing it between himself and the light, will be able to make out the mesenteries through the body-wall of the column, which is rather transparent towards the top. It will be observed that of the tentacles immediately adjoining the margin, three spring from between each pair of mesenteries ; of these three tentacles two are much smaller than the third, and are situated one on either side of it: these smaller tentacles are those which have the scarlet or orange core. The lines of the insertions of the mesenteries are continuous throughout the entire body-wall of the column.
One specimen of Sagartia venusta which we kept in confinement displayed a curious condition of the tentacles. As Gosse has observed (Actin. Brit., p. 60), the colour of the tentacles is generally more pellucid at the tip, and more or less opaque in the middle portion. At the junction of these opaque and pellucid regions the tentacles of the specimen in question frequently used to exhibit a deep constriction. When present, this constriction always occurred exactly at the line of demarcation between the pellucid and opaque portions of the tentacle.
We have found this species at Monkstown and Dalkey attached to the under surfaces of granite boulders. Many specimens had some of their tentacles forked or knobbed.
This species occurs pretty frequently at Malahide and Howth : the specimens to be obtained at these places are exactly similar to those found in Torbay, a locality for the species known to Gosse. Cylista viduata in confinement frequently lies non-adherent at the bottom of the tank; sometimes with its base protruded and swollen, like the physa of the free genera, Peachia and Halcampa. At times it envelopes itself in a thin vesture of slime with confervoid matter imbedded in it, somewhat recalling the habit of the genus Edwardsia. Gosse describes the emission of ova and spermatozoa by the allied species Cylista undata in the month of May; we have witnessed a similar phenomenon in the case of C. viduata, and at the same season of the
hora and spermato 1. the spermatozormatozoa being ther
year. Both ova and spermatozoa were ejected together, at the same moment, by the same individual; the spermatozoa were in two states
-some free, some clustered, the clusters of spermatozoa being each about the same size as an ovum. The ova were not ciliated; neither were they ribbed or ridged, like those which we describe in the case of Actinia equina. The ova decomposed, and we failed to rear any of them. At the time of the emission of the generative products, and for a few days subsequently, the tips of the tentacles were filled with spermatozoa so as to be quite opaque. We have never seen any
begunten op or woontaneous instance of this species been propagated by spontaneous separation of portions of the base. (See Gosse, Actin. Brit., p. 110.)
We have no information derived from transverse sections respecting the arrangement of the mesenteries in this species. The base, however, of one specimen we had was so transparent that it was very easy to see the insertions in this part. The mesenteries followed a perfectly regular hexamerous arrangement. Six primary pairs ran the whole way into the centre ; six secondary pairs lay between these, and then there came in regular position twelve tertiary and twenty-four quaternary pairs ; none of the mesenteries, except the primary pairs, ran the whole way into the centre from the margin of the base.
We have found several large specimens, some having white, and some blue marginal spherules, with these organs lobed and warted in an irregular manner. One or two specimens, in which the majority of the spherules were white, had the remainder of these organs red, of the same hue as the rest of the body. A similar departure from the normal uniform colouring of the spherules occurs at times in specimens where the majority of these organs are blue. We have found one or two specimens in which all the spherules were red. As the individuals presenting these variations were in other respects identical, it would seem to be absolutely concluded that Gosse is right in refusing to follow Cocks and Dalyell in establishing a species A. chiococca. Each of the marginal spherules contains a prolongation of the general body cavity; and, consequently, these organs can be dilated at the will of the animal. One specimen which we kept in confinement had long fixed its home near the top of the tank, on one of the sides adjoining the glass front. One day we saw that it had its spherules much dilated, and those that were nearest the glass came in contact with it When these organs contracted and
withdrew from contact with the glass, we observed that they had left considerable portions of themselves remaining behind, and forming conspicuous blue spots adhering to the glass. On examination of these blue spots, we found them to consist chiefly of the spindleshaped cells described by Hollard. (Ann. d. Sci. Nat. Zool., 3 ser., vol. XV., p. 272.) The anemone had evidently been engaged in an attempt to sting the glass-front of the tank.
In spring-time mature specimens of this species give birth to numerous ciliated embryos. These are at first minute oval objects, measuring about 1 mm. in the least diameter. But they quickly increase in size, and at the end of a week or ten days the tentacles form at one end, round a depression which has been previously developed. When they are first ejected the embryos are marked with eight or nine obliquely placed ridges, like the skin-markings on the top and front of the fingers of the human hand.
We have cut a series of transverse sections in a large number of very young specimens. The result of these sections was to confirm what we have already stated in the case of Bunodes verrucosa (Proc. Roy. Dub. Soc., N. S., vol. vi., pp. 322, 323), and also to show that those mesenteries which do not arise in pairs start from the angle between the oral disk and the body-wall, and grow downward ; while those mesenteries which arise in pairs start from the angle between the pedal disk and the body-wall, and grow upward.
A vertical section of a young specimen in which the sphincter muscle was hardly yet developed showed that the epithelium of the @sophagus is directly continuous with that on the middle lobe of the perfect mesenteries, and exactly similar in appearance.
tween the ories which arise, and gro
It is not uncommon to find a small species of Pycnogonum sp. ?clinging to Peachia hastata just below the tentacles. On one occasion we separated the companions : the anemone at the time was attached to the glass by the suckers on its column on the opposite side to where the Pycnogonum was fixed. The little Pycnogonum was grasped in a forceps, but it adhered so firmly that it did not let go its hold till the anemone was stretched out to at least twice its usual diameter. Curiously enough, the Peachia seemed to suffer no inconvenience from the tugging to which it was subjected.
It would seem that there are either but weak stinging cells or else none at all in the disk and tentacles of this anemone; for gobies and