By Professor Balfour.-From the Author. 2. Transactions of the Botanical Society. Vol. VI., Part III. Edinburgh, 1860.-From the Society. 3. On the Tertiary Deposits associated with Trap-Rock in the East Indies. By the Rev. Stephen Hislop.-From the Author. 4. On the Arrangement of the Muscular Fibres of the Ventricular Portion of the Heart of the Mammal. By James Pettigrew, Esq.-From the Author. 5. The Quarterly Journal of the Geological Society. No. 62, May 1860. Vol. XVI., Part II.-From the Society. 6. Jahrbuch der Kaiserlich-Königlichen. Geologischen Reichsanstalt, 1860. XI. Jahrgang, No. I., Jan., Feb., Marz. Wien.-From the Imperial Geological Society of Vienna. The Communications read were as follows:

I. Observations on British Zoophytes and Protozoa.

On Atractylis palliata and coccinea (new species). By T. STRETHILL WRIGHT, M.D.

1. Atractylis palliata, n. sp. Pl. XI. fig. 6.

Polypidom creeping, closely reticulate. Polyps fusiform, shortly stalked, minute, white, with eight alternating tentacles; body of polyp clothed with a thick layer of 'colletoderm.' Free medusoids springing from meshes of polypary, with four-lipped peduncle; four lateral canals; two long marginal tentacles and two tentacular tubercles alternately placed.

This zoophyte was found on a shell inhabited by Pagurus Bernhardus, at Granton. When first observed, its closelyset and dense white polyps, surrounded by their gelatinous envelopes, were mistaken for a mass of minute ova. These envelopes cover the whole of the body of the polyps up to the border of the mouth, and consist of an exaggerated development of the gelatinous coat which probably exists on the polypidom and body of all the Hydroidæ, in some as a delicate epidermis, in others (as in Bimeria vestita and the subject of this notice) as a thick, imputrescible coatthe "colletoderm."

The Medusoids (Pl. XI. fig. 7) are of great size when compared with the very minute polyp, and resemble exactly those of Atractylis repens. I have not witnessed any further development in them after their separation from the zoophyte. In those of A. repens, when kept alive for some time, the two tentacular tubercles put forth short tentacles,

and four other tubercles appear on the marginal canal, as shown in fig. 8-a change analogous to that undergone in Bougainvillea Britannica.

2. Atractylis coccinea, n. sp.

Polypidom creeping, widely reticulate. Polyp fusiform, set at an obtuse angle to its stalk, rich crimson or pink, with eight alternating tentacles, four long and four short.

This zoophyte was found at Inchgarvie in August last, growing on the roots of Laminaria saccharina. The polypary consists of an open network of milk-white fibres, which closely invests the branches of the root. From this net work the polyp-stems are given off, each about a quarter of an inch in length, of a rich pinkish cream-colour, and bearing at its summit a single crimson polyp with a double row of transparent colourless tentacles. The body of the polyp is fusiform, sometimes nearly cylindrical, and consists of an endoderm having its cells laden with granules of the richest carmine-colour, covered by an ectoderm of transparent white-a white blond dress over a crimson satin petticoat. The polyps, like others of this class, have the habit of turning themselves inside out, when the internal surface of the deep-coloured velvety endoderm is readily observed. such occasions masses of granular matter are frequently ejected, which are composed of small pigment-globules filled with crimson fluid. The tentacles are eight in number, four of which are long and held nearly erect, and alternate with the rest, which are shorter and more expanded. The thread-cells are inconspicuous.

On

This beautiful little zoophyte, when seen with a single lens, presents a perfect garden of minute animal flowers covering the roots of the sea-weed. The reproductive apparatus was not observed.

3. On Rhizopod Structure.

One of the most interesting and important questions of the day to the comparative physiologist is that of the constitution of Rhizopod structure. The Foraminiferous or Rhizopod animals are before our microscopic eye every day. We

VOL. II.

2 K

see their beautifully chambered shells imitating some of the most graceful objects of nature and art,-the living streams of nearly fluid sarcode, of which they are composed, flowing forth from the almost invisible pores of their shells, uniting with each other, and forming glairy masses, and reticulations, and expansions, which absorb animal matter coming in contact with them,-single and compound animals building their aggregated homes in the most graceful lines and spirals, single dwellings and populous towns slowly moving along, of which the inhabitants are but patches of transparent slime,-vast Polythalamian cities, where the huge primordial Rhizopods reign, surrounded by the multitudes of their dwarfed descendants, in widening circles and triple tiers. Such is Rhizopod life. At present no true generative elements have been recorded as discovered in the Rhizopods, though Carpenter and Schultze have noticed bodies which they have suspected to be ova. In the autumn of 1859 I was preparing a number of specimens of Hydractinia for the microscope. They were first soaked in whisky for several weeks, then immersed in dilute nitric acid to remove them. from the crab's shell, and finally washed in strong spirit, and put up in Canada balsam. On examining one of these preparations under the microscope, it was found that two specimens of Truncatulina had been accidentally prepared at the same time. The development of Truncatulina commences with a single cell; this multiplies by gemmation in series until a colony of animals is formed, each larger than its predecessor, arranged in a spiral, somewhat resembling the shell of the Nautilus. In the Nautilus, the last chamber of the shell only is occupied; but in Truncatulina every chamber contains its tenant, while the whole colony are united by a band of sarcode, which passes from chamber to chamber along the inner curvature of the shell. All the cells or houses in this Rhizopod town are full of minute pores, from which the inhabitants protrude their delicate arms of slime in search of prey, or to move the assemblage from place to place. When the Truncatulina is treated as before mentioned, the shell is removed, and the separate zooids appear united by their connecting band. One of the

two Truncatulinas, when examined by aid of the microscope, was found to consist entirely of homogeneous matter; but the other presented a far different appearance. Its segments or zooids, and their connecting bands, all appeared to be enclosed in a well-defined membrane. Each segment was nearly destitute of sarcode, and contained a highly refractive body, in which appeared, with the utmost distinctness, a germinal vesicle or spot. I can regard this body only as a true egg, which has been developed at the expense of the sarcodal element of the segments, in many of which the reproductive process is occurring simultaneously. Yet it may be objected that the ova in the larger segments are greatly larger than the young or original animals of Truncatulina. In some animals, however, as in Spongilla, Gregorina, &c., many individuals are produced from a single egg; and it is not improbable that a process of great division of the egg or swarming may take place in Truncatulina, by which a great number of animals may be produced from each segment.

II. Note on the Occurrence of Trilobites in the Carboniferous Limestones of Fifeshire. By R. H. TRAQUAIR, Esq. (Specimens exhibited.) In the neighbourhood of St Andrews, Fifeshire, remains of a trilobite (Griffithides mucronatus-M'Coy) are pretty common in the shale overlying the thick bed of limestone worked at Ladeddie, Wilkieston, and Newbigging, and belonging to the Carboniferous Limestone series.

At each of these quarries the limestone itself is hard, blue, and crystalline, and contains but few fossils; but these, consisting of corals, polyzoa, shells, and trilobites, are abundant in the overlying shale, though generally in a very fragmentary condition. This is especially the case at Ladeddie, and, combined with the soft and friable consistency of the shale, renders it difficult to obtain good specimens from that locality. At Wilkieston, however, the shale has assumed a more firm and slaty aspect, and the contained fossils are in a much better state of preservation.

The trilobites occur for the most part in a very disjointed and fragmentary condition, entire specimens with head, thoracic segments, and caudal shield in apposition, being

very rarely met with. By far the most abundant relics are the caudal shields, or pygidia, which are sometimes found two or three lying together on one small piece of shale. The head is of rarer occurrence; it is sometimes found entire, but very frequently disjointed, the glabella, or central part, lying apart from the two lateral cephalic shields. Of entire trilobites I found one very good specimen (in the extended position) at Wilkieston, and two doubled or rolled up (after the manner of certain Oniscide when alarmed). Mr Walker, of the University Museum, St Andrews, showed me also a very good specimen of the entire animal extended, which he obtained at Ladeddie.

III, Note on the Exposure of the Liberton Old Red Sandstone Conglomerate Bed, in a Quarry recently opened near the Grange House, Newington. By ANDREW TAYLOR, Esq.

The existence of the conglomerate, only visible for a few yards at Liberton Brae, and sinking to the E.S.E. at about 35°, was noted, so far back as 1839, by Cunningham, in his prize essay on the Geology of the Lothians. In the excellent descriptive catalogue of the rock specimens in the Jermyn Street Museum, Mr Geikie catalogues this rock as a calcareous conglomerate; being one of the passage beds between the Old Red Sandstone and Lower Carboniferous series; the basis being stated to be a calcareous sand, with the pebbles generally well rounded, and consisting partly of a compact, cherty limestone, partly of different felstones, and sometimes of various gray micaceous grits. The stratigraphical importance of this bed in our local geology has likewise been duly recognised in the recently published geological survey map of the district; in which it has a distinctive colour and boundary assigned to it, which is made to terminate at the margin of the great fault, marked as running from the northern base of the Pentland range to near Wester Duddingston. The strata north of this fault-line, and on which Newington with the rest of the city is built, are, on the other hand, pectorially distinguished as decidedly Lower Carboniferous, and beneath the horizon of the Burdiehouse limestone. In the field to the west of that section of the Lover's Loan which runs past the