Narrative of the Voyage of H.M.S. Rattlesnake, Commanded By the Late Captain Owe - Volume 1 - John MacGillivray (feel good books to read TXT) 📗

less distinct than in C. pumicosa. As in that species, some of the cells are furnished with an avicularium, and others unprovided with that appendage; and again, some cells support an ovicell, whilst others do not. The mouth of the unarmed cells in both species is more or less circular and plain, but in C. bilabiata, even in the unarmed cells, the mouth is occasionally distinctly bilabiate. In C. pumicosa the avicularium is placed subapically on a solitary posterior obtuse mucro, but in C. bilabiata there are two such processes longer and more pointed, one in front and the other behind the mouth; the avicularium, as in the former case, being placed immediately below the apex of the posterior mucro. The ovicells also differ very much. In C. pumicosa this organ presents several rather large circular spots or perforations ? whilst in C. bilabiata it exhibits a scutiform or horseshoe-shaped area, marked with several transverse lines on each side of a middle longitudinal line.

Fam. 7. GEMELLARIADAE.

Cells opposite, in pairs.

22. DIDYMIA, n. gen. Table 1 figure 6.

Cells joined side by side; opening large, oval; mouth subapical, central. No avicularium. Ovicells contained within a cell, which is central at each bifurcation.

1. Didymia simplex, n. sp. Table 1 figure 6.

Cells oblong, narrowed below, broad and truncate, with an angle externally above. Back marked with transverse rugae.

Habitat: Bass Strait, 45 fathoms.

A fine species, growing in loosely-branched phytoid fronds, to a height of several inches. In some (dried) specimens the branches are a little incurved, but not in all. The situation of the ovicell is peculiar. It is contained within the upper part of a cell placed between, or rather in front of the pair, from which the two branches at a bifurcation take their origin. The ovigerous cell differs widely in form from the others, being pyriform, and much attenuated below; and the orifice is below the middle. The upper compartment, in which the ovicell or sac itself is lodged, appears to be separated from the lower by a transverse diaphragm.

23. DIMETOPIA, n. gen. Table 1 figures 7 to 9.

Cells joined back to back; the mouths of each alternate pair looking in the same direction, and at rightangles to the intermediate pair.

1. D. spicata, n. sp. Table 1 figure 9.

Cells infundibuliform. Margin of opening much thickened, with six equidistant, elongated pointed spines.

Habitat: Bass Strait, 45 fathoms.

White, transparent, forming thick tufts about 1 1/2 to 2 inches in height. The same species also occurs in New Zealand.

2. D. cornuta, n. sp. Table 1 figures 7 and 8.

Cells suddenly contracted about the middle. Opening oval, wide above; margins slightly thickened with a short thick conical horn on each side above, and a long projecting spine (rarely two) in front below.

Habitat: Bass Strait, 45 fathoms.

Branches narrower than in the preceding species. Colour yellowish. Tufts loose; ovicell small in proportion to the size of the cells. It is placed immediately above and behind the upper margin of the opening of the cell to which it belongs.

Suborder 3. CTENOSTOMATA.

Fam. 1. VESICULARIADAE. Cells tubular, horny.

24. AMATHIA, Lamouroux.

1. A. biseriata, Krauss. Corall. der Sudsee, page 23. Figure 1 a, b, c.

Habitat: Swan Island, Banks Strait.

The biserial arrangement of the cells is not a sufficient character, because in Amathia cornuta (Lamouroux) the cells are also biserial as well as in another South African species, very like the Australian form probably intended by Krauss, but apparently different from it. In the South African form the cells are shorter, narrower, and more cylindrical, and the branches are terminated by two lanceolate tags, which are not present in the Australian species, in which latter the cells also are wider, longer, and prismatic, or subhexagonal, with very thin walls.

...

SERTULARIAN ZOOPHYTES.

The number of species of Sertularian Zoophytes comprised in this collection amounts to thirty-one, belonging to five genera, all of which appear to be common to both the Northern and Southern hemispheres; and four are European types. The fifth, Pasythea, is stated by Lamouroux, to be found on Fucus natans and in the West Indies; so that the present collection does not present any peculiar Australian generic form. It is far otherwise, however, with respect to the species. Of these three only are found in the European seas namely:

Sertularia operculata. Campanularia dumosa. Campanularia volubilis ?

Of which the first is a perfect cosmopolite, and the last is perhaps doubtful.

There are also, what is much more strange, not more than three species which I have been enabled to trace to any other locality, even in the Southern hemisphere. These are:

Sertularia elongata. Sertularia divaricata, n. sp. Plumularia macgillivrai, n. sp.

The first occurring in New Zealand; the second on the south coast of Patagonia and in the Straits of Magellan; and the third (which, however, is not, strictly speaking, an Australian form, having been procured in the Louisiade Archipelago) in the Philippine Islands. With these six exceptions, the whole number of species would therefore, to a certain extent, appear to be characteristic of the Australian seas.

Of the thirty-one species, it appears strange that not less than twenty-five should here be described as new; and there can be no doubt many so described are included under the vague and uncertain descriptions of Lamarck and Lamouroux; but, in the absence of authentic specimens, or trustworthy figures, I have found it impossible to identify satisfactorily the species described by them, and have therefore thought it better to assign new names rather than to apply former ones, which would in all probability prove incorrect. It is hoped, at all events, that the descriptions here given will be found sufficient to prevent any misconception of what is intended in the following catalogue.

The mode in which the species are arranged will be seen from the following synoptical arrangement:

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SYNOPTICAL ARRANGEMENT OF THE GENERA AND SPECIES OF SERTULARIAN ZOOPHYTES COLLECTED ON THE VOYAGE OF THE RATTLESNAKE.

Order. ANTHOZOA HYDROIDA. Sub-order. SERTULARINA. Fam. 1. SERTULARIADAE. Gen. 1. Sertularia. § 1. Cells alternate (Sertularia). (a) Cells distichous. 1. S. elongata. 2. S. divaricata, n. sp. 3. S. crisoides. (b) Cells secund. 4. S. pristis. § 2. Cells opposite (Dynamena). (a) Cells distichous. 5. S. subcarinata, n. sp. 6. S. patula, n. sp. 7. S. orthogonia, n. sp. 8. S. mutulata, n. sp. 9. S. operculata. 10. S. divergens, n. sp. 11. S. trigonostoma, n. sp. 12. S. digitalis, n. sp. 13. S. loculosa, n. sp. 14. S. unguiculata, n. sp. 15. S. tridentata, n. sp. 2. Pasythea. 16. P. hexodon, n. sp. 3. Plumularia. § 1. Angiocarpeae. 17. P. huxleyi, n. sp. 18. P. hians, n. sp. 19. P. delicatula, n. sp. 20. P. aurita, n. sp. 21. P. brevirostris, n. sp. 22. P. ramosa, n. sp. 23. P. divaricata, n. sp. 24. P. phoenicea, n. sp. 25. P. longicornis, n. sp. 26. P. macgillivrayi, n. sp. § 2. Gymnocarpeae. 27. P. effusa, n. sp. 28. P. campanula, n. sp. Fam. 2. CAMPANULARIADAE. 4. Campanularia. 29. C. volubilis (?) 30. C. dumosa. 5. Laomedea. 31. L. torressii, n. sp.

Order. ANTHOZOA HYDROIDA.

Suborder. SERTULARINA.

Fam. 1. SERTULARIADAE.

Gen. 1. Sertularia, Linnaeus.

1. Cells alternate (Sertularia).

a. Cells distichous.

1. S. elongata, Lamouroux.

Habitat: Swan Island, Banks Strait, thrown on the beach. Port Dalrymple, on stones at low water. (Also New Zealand.)

2. S. divaricata, n. sp.

Cells urceolate-subtubular, or very little contracted towards the mouth, often adnate to the rachis nearly their whole length; mouth looking upwards, with three large acute teeth, two lateral, and one rather longer than the others, and slightly recurved, above. Ovicells -- ?

Habitat: Bass Strait, 45 fathoms, dead shells.

Colour dirty yellowish white; polypidom branched, from a common stem; branches irregular (?) straggling, pinnate and bipinnate, pinnae and pinnules divaricate at rightangles, alternate; rachis flexuose, or with an angle at the origin of each pinna. The cells are placed at wide distances apart; small and adnate very nearly to the top. The mouth circular, with three large teeth, the one above frequently obscured by adventitious substances, very acute, ascending, and a little recurved.

Sertul. gayi. (Lamouroux. Exp. page 12 plate 66 figure 89 has four teeth.)

This species occurs also on the south coast of Patagonia, and the Straits of Magellan; in the latter locality, however, the habit is much more robust.

3. S. crisioides, Lamouroux. (Dynamena.)

Cells adnate, conical, slightly curved, truncate at bottom, narrow at top; mouth vertical, external.

Habitat: Off Cumberland Islands, 27 fathoms.

Very like a Thuiaria, but the cells are not immersed, though very closely adnate, and the outer angle of the square base of each cell is in contact with the upper and back part of the one below it, so that a small triangular space or opening is left below each cell. The branches are very regularly alternate; and the polypidom is of a light brownish colour.

(b) Cells secund.

4. S. pristis, (B.).

Idia pristis, Lamouroux.

Cells tubular, all contiguous or adnate to each other, and to the rachis, upper half curved laterally, lower half closely adnate, almost immersed in the rachis; mouth looking upwards, rounded, expanded, almost infundibuliform, border slightly scalloped towards the rachis, and projecting externally. Ovicell cyathiform, long narrow with circular rugae. Mouth as large as the diameter of the cup, margin very slightly everted.

Habitat: Prince of Wales Channel, Torres Strait, 9 fathoms. Off Cumberland Islands, in 27 fathoms, fine grey mud.

I see no reason why the present species should not come under Sertularia. It is peculiar from the position and extreme contiguity of the alternate cells. The ovicells arise from the back of the rachis towards the side. When viewed posteriorly, the cells are seen through the transparent rachis, and it might thus at first sight appear as if the rachis itself were cellular and not tubular, but such is not the case. The tube is wide and continuous from end to end.

2. Cells opposite (sometimes alternate on the stem). (Dynamena).

(a) Cells distichous.

5. S. subcarinata, n. sp.

Cells tubular, upper half divergent, ascending. Mouth looking upwards, circular, with an anterior and two lateral broad, expanding teeth. A narrow angular line or keel down the front of the cell. Ovicell -- ?

Habitat: Bass Strait, 45 fathoms dead shells.

Colour white, transparent, growth small, straggling. Branches irregular, divaricate nearly at rightangles, subalternate. The three expanding teeth and the anterior ridge or keel, besides its habit, distinguish it from a Tasmanian species with which alone can it be confounded. The cells are large.

6. S. patula, n. sp.

Cells tubular, upper third free, divergent ascending. Mouth perfectly round, looking upwards and outwards, margin entire everted. Ovicell -- ?

Habitat: Bass Strait, 45 fathoms, dead shells.

Colour whitish. A small parasitic species, with opposite branches.

7. S. Orthogonia, n. sp.

Cells tubular, nearly half free, divergent laterally at a right angle. Mouth looking directly outwards, border entire, slightly everted. Ovicell -- ?

Habitat: Prince of Wales Channel, Torres Strait, parasitic upon S. pristis.

Very like the preceding in habit and size, of which it may possibly prove to be a variety. The cells, however, throughout the whole of the polypidom are of precisely the same character, in each form, and exhibit no intermediate steps. In the present species the cells are much longer, rather narrower, and the upper half is turned out abruptly at a rightangle, whilst in the former they ascend at an angle of 45 degrees, and the