lo <5r Natural History Museum Library 000120079 THE VOYAGE OF H.M.S. CHALLENGER. NARRATI VE-VOL. I. SECOND PART. . 7° ! PERMANENT PhOTOT ' Crater of Kilauea, Mona Loa, REPORT ON THE SCIENTIFIC RESULTS OF THE VOYAGE OF H.M.S. CHALLENGER DURING THE YEARS i 8 7 3-7 6 UNDER THE COMMAND OF Captain GEORGE S. NARES, R.N., F.R.S. AND THE LATE Captain FRANK TOURLE THOMSON, R.N. PREPARED UNDER THE SUPERINTENDENCE OF THE LATE Sir C. WYVILLE THOMSON, Knt., F.R.S., &c. REGIUS PROFESSOR OF NATURAL HISTORY IN THE UNIVERSITY OF EDINBURGH DIRECTOR OF THE CIVILIAN SCIENTIFIC STAFF ON BOARD AND NOW OF JOHN MURRAY ONE OF THE NATURALISTS OF THE EXPEDITION uv Narrative— Vol. I. SECOND PART. IPublts&eb bp <0rber of !£>er jPlajestp’s <0obernment PRINTED FOR HER MAJESTY’S STATIONERY OFFICE AND SOLD BY LONDON LONGMANS & CO.; JOHN MURRAY; MACMILLAN & CO.; SIMPKIN, MARSHALL. & CO. TRUBNER & CO.; E. STANFORD; J. D. POTTER; and KEGAN PAUL, TRENCH, & CO. EDINBURGH ADAM & CHARLES BLACK and DOUGLAS & FOULIS. DUBLIN A. THOM & CO. and HODGES, FIGGIS, & CO. I885 Price ( Parts First and Second ) £6, 16s. 6d. I PRINTED BY JSfE.lTL AND COMPANY, EDINBURGH, FOR HER MAJESTY'S STATIONERY OFFICE. NARRATIVE OF THE CRUISE OF H.M.S. CHALLENGER WITH A GENERAL ACCOUNT OF THE SCIENTIFIC RESULTS OF THE EXPEDITION BY Staff-Commander T. H. TIZARD, R.N.; Professor H. N. MOSELEY, F.R.S.; Mr. J. Y. BUCHANAN, M.A.; and Mr. JOHN MURRAY, Ph.D.; MEMBERS OF THE EXPEDITION. Partly Illustrated by Dr. J. J. WILD, Artist to the Expedition. Y> CONTENTS OF SECOND PART. CHAPTER XIII. Fiji Islands to the New Hebrides Islands — Halobates — Api — The Macrura — Raine Island — Cape York — Arrou Islands — Ki Islands — Banda Group, .... CHAPTER XIV. Banda Islands — The Monaxonida — Banda to Amboina — The Actiniaria — Amboina — Mimicry in Butterflies and Moths — The Brachyura — Amboina to Ternate — Ternate — The Medusae, CHAPTER XV. Ternate to Samboangan — The Asteroidea — Samboangan to Ilo Ilo — The Amphipoda — Ilo Ilo to Manila — The Lamellibranchiata — Manila to Hong Kong— The Annelida — The Calcarea and Keratosa, ............ CHAPTER XVL Hong Kong to Manila and Zebu — Mactan and Zebu — Zebu to Camiguin Island and Sambo- angan— Samboangan — Samboangan to Humboldt Bay — The Polyzoa — Cepbalodiscus — Humboldt Bay — Humboldt Bay to the Admiralty Islands — The Alcyonaria — The Nudibranchiata, CHAPTER XVII. The Admiralty Islands — History of their Discovery — Description of Nares Harbour— General Appearance of the Islands and Botany — Natives — Their Houses, Habits, Customs, Ornaments, Weapons, and Implements — Zoology — Polynesian Races, ...... CHAPTER XVIII. Admiralty Islands to Japan — The Schizopoda, Cumacea, and Phyllocarida — Japan — The Japan Stream — Japan to the Sandwich Islands — The Hydroida — Honolulu — Hawaii — Sandwich Islands to Tahiti — Dr. Rudolf von Willemoes-Suhm — Tahiti — Structure of Coral Reefs — The Corals, ............ CHAPTER XIX. Tahiti to Juan Fernandez — Manganese Nodules, Sharks’ Teeth, Zeolites, and Cosmic Spherules in the Deposits of the Central South Pacific — The Stomatopoda — Historical Account of Juan Fernandez — Physical Features — Botany and Zoology — The Nemertea — -Juan Fernandez to Val- paraiso— The Foraminifera — Valparaiso — The Copepoda and Ostracoda, . J PAGE 511-560 561-603 604-645 646-695 696-733 734-800 801-848 viii THE VOYAGE OE H.M.S. CHALLENGER. CHAPTER XX. Valparaiso to Cape Tres Montes — The Cirripedia and Pyenegqnida — Through the Messier Channel, Sarmiento Channel, and the Strait of Magellan to the Falkland Islands— The Isopoda — The Falkland Islands — Fossils — The Scaphopoda and Gasteropoda — The Anomura, CHAPTER XXI. Falkland Islands to Monte Video — The Deep-Sea Fishes — Monte Video — The Gephyrea — Monte Video to Ascension — Description of the Deposits — On Deep-Sea Deposits in General — Ascension — Ascension to Porto Praya— Pelagic Diatoms — Infusoria — Pyrocystis — Coccospheres and Rhabdospheres — Bathybius — Cape Verde Islands to England — Synoptical Table of the Voyage — The Botany of the Expedition — Challenger Collections and Publications, CHAPTER XXII. Density of Sea Water — Composition of Ocean Water Salts — Geographical and Bathymetrical Distribution of Specific Gravity — Carbonic Acid, Nitrogen, and Oxygen in Sea Water — Discussion of Meteorological Observations as bearing on Oceanic Circulation, ..... APPENDICES. Appendix I. Explanation of Symbols and Abbreviations used in the Charts and Diagrams, II. Revised Table showing the positions of the Soundings obtained by H.M.S. Challenger, the Temperature and Specific Gravity of the Surface and Bottom Water, and the Stations where Serial Temperatures, Trawlings, and Dredgings were procured, III. Report on the Chronometers supplied to, and the Meridian Distances obtained by H.M.S. Challenger, between the 1st December 1872 and the 12th June 1876, by Staff-Commander T. H. Tizard, R.N. ... . IV. Report on the Health of the Crew of H.M.S. Challenger, during the years 1873-76. By Fleet-Surgeon George Maclean, R.N. ....... V. Chemical Analyses, .......... VI. Bibliography, giving the Titles of Books, Reports, and Memoirs referring to the Results of the Challenger Expedition, ........ VII. List of Reports on the Scientific Results of the Expedition, .... VIII. Letters addressed by the Admiralty to the Captain of H.M.S. Challenger, and the Director of the Civilian Scientific Staff, after the Arrival of the Expedition in England, . Index, PAGE 849-901 902-947 948-1003 1005 1007-1015 1017-1026 1027-1031 1033-1051 1053-1063 1065-1072 1073 1075-1110 (For Lid of Illustrations in this Part see First Part.) H.M. S. Challenger — Shortening Sail to Sound. CHAPTER XT IT. Fiji Islands to the New Hebrides Islands — Halobates — Api — The Macrura — Koine Island — Cape York Afrou Islands — Ivi Islands — Banda Group. Fiji Islands to the New Hebrides. On the 11th August 1874, at, G p.m.. after swinging for magnetic purposes, the ship finally left the Fiji Islands, all sail being made to the westward. Mount Washington was in sight all day. On the 12th, at 6 A.M.. a sounding, trawling, and temperatures were taken in 1350 fathoms, at Station 175 (see Sheet 27). The trawl caught at the bottom, but was successfully cleared and brought to the surface at 3 p.m. On the 15th another sounding and serial temperatures were taken in 1450 fathoms. From the 11th to the 15th, wet changeable weather was experienced, the wind blowing chiefly from N.E., but never remaining steady. On the 13th the fore topgallant mast and flying jib-boom were carried away in a rain squall before Sail could be shortened. The deposits at 1350 and 1450 fathoms were Globigerina oozes of a reddish colour, closely resembling the red clays in that respect. They contained respectively 45 and 61 per cent, of carbonate of lime, consisting of Rhabdoliths, Coccolitlis, the shells of Globi- gerina, Orbulina, Hastigerina, Pvlvinnlina, Sphceroidina , Pullenia, and some bottom- living species. A few of the Globigerina shells had still the delicate spines attached as. in the specimens taken on the surface. The absence of Pteropod, Heteropod, and other pelagic Molluscan shells from these deposits is somewhat remarkable, for they were very abundant (XARK. CHALL. EXP. VOL. I. 1885.) 65 512 THE VOYAGE OF H.M.S. CHALLENGER. on the surface, and at a similar depth and latitude in the Atlantic they were usually present in considerable numbers. The Foraminifera shells were in some instances quite white, or with a rosy tinge as if lately fallen from the surface, but the great majority were brown coloured, and in some instances black, from a deposit of oxide of manganese on their surface. When one of these dark coloured shells from 1450 fathoms is broken, three zones can be distinguished : at the centre an internal cast of the shell, then the white carbonate of lime shell itself, and outside this an external cast of the same nature and aspect as the internal one, to which it is connected by little red pillars which fill up the foramina of the shell. These casts do not appear to be formed by a simple filling of the shell, but to be due to a chemical combination. There were in these deposits none of the smooth pale yellow and green casts so abundant in the green muds along continental shores. If the brown casts be treated with warm hydrochloric acid and the iron thus extracted, a number of colourless globules are obtained, which have resisted the action of the acid. It has been found that these casts consist of a hydrated silicate containing alumina, lime, magnesia, and alkalies. The mean diameter of the minerals in these deposits— felspars, black mica, augite, hornblende, and magnetite — rarely exceeded 0'05 mm. The great bulk of the residue, however, after removal of the lime, consisted of pumice stone in a fine state of division, with argillaceous matter. Radiolarians and Diatoms made up about 2 per cent, of the whole deposit. The trawling at 1350 fathoms gave a few deep-sea animals, many rounded fragments of pumice covered with oxide of manganese, and the branch of a tree several feet in length which was carbonised in some places. There were many very productive hauls with the surface nets between the Fiji Islands and the New Hebrides, Pteropods, Heteropods, and pelagic Foraminifera being specially abundant. With the exception of a very large cylindrical species of Etmodiscus, Diatoms were very rare both on the surface and at the bottom. It was observed that the larger Foraminifera, such as Sphceroiclina dehiscent, Pulvimdina menardii, and thick shelled Orbidince, were procured in greatest abundance when the tow-net was dragged at a depth of 80 or 100 fathoms. On one occasion the otter trawl was towed for some time from the lower boom, a short distance beneath the surface. It was not so successful in catching fish as was hoped ; it contained, however, large masses and strings of jelly, which on examination turned out to be the eggs of a Cephalopod. Flying Fish ( Exocetus ) were especially abundant during this trip, and at night frequently dashed on board ship near the exposed lights. Holoibates. — Specimens of this insect, of which very many were collected during the cruise, were especially abundant on the surface between the Fijis and the New Hebrides. This group of Hemiptera is interesting as containing (along with the ollied genus NARRATIVE OF THE CRUISE. 513 Halobatodes) the only insects with an organisation adapted to a truly pelagic mode of life. The head, in addition to the antennae (fig. 179, a), bears three tubercles on either side, surmounted by a single hair, but of unknown function. The mandibles are pointed and serrated, and serve to puncture the creatures upon which they feed, whilst they suck out the juices through a kind of tubular proboscis formed by the united maxillae. The thorax forms by far the largest part of the body ; the first segment is transverse and collar-like, the second and third elongated and fused, and produced behind and below into the acetabula with which the hinder legs are articulated (fig. 179, $ , $ ). The abdomen is larger in the male than in the female ; it consists of six ring-like segments followed by three others specially modified (fig. 179, g,g.a). The abdomen of the female consists of Fig. 179. —Halobates wiillerstorffi, Frauenfeld. 6 , Male, upper side ; ? , outline of the body of the female ; a , antenna ; ft, front tarsus ; fta, front tarsus of the larva : m.t, middle tibia and tarsus ; g , genital segments of the male, from above ; g.a, the same in profile. the same number of segments and carries an ovipositor made up of four valves ; in both sexes the ventral surface of the first segment bears a curious tubercle whose extremity is pierced by a transverse perforation. The fore-legs are short, and for the greater part' of their length lie well in advance of the body, without being raptorial they are fitted for grasping ; and the second joint of the tarsus is furnished with two curved sharp-pointed claws, as well as a thin ribbon-like process (fig. 179 , ft). The two hinder legs are long, and by their means the little creatures scud over the surface of the water. The tarsus of the middle legs (fig. 179, m.t) has a fringe of long hairs, which probably serves to aid the animal in swimming or to prevent its being so readily driven by the wind. 514 THE VOYAGE OE H.M.S. CHALLENGER. The genus was first founded by Eschscholtz in 1822 for the reception of three species taken during von Kotzebue’s voyage round the world ; at present it appears from the investigations of Dr. F. Buchanan White1 to contain eleven species, of which six were discovered by the Challenger. The allied genus Halobatodes contains four species, two being new, but only one is certainly known to be marine. They appear to live upon the juices of dead animals floating upon the surface. Some species, at all events, have the power of diving, and have been seen to do so in order to avoid being captured. Their distribution is very wide, for they occur in all the great oceans. Mr. Murray noted their occurrence twenty-one times in the Atlantic between the parallels of 35° N. and 20° S., and thirty-eight times in the Pacific between lats. 37° N. and 23° S., so that they would seem to be confined to the warmer waters of the ocean. The region between the eastern part of the Indian Ocean and the Western Pacific seems to be the metropolis of the genus, nine out of the eleven known species occurring there, and five nowhere else ; it is also interesting to note that the species of the genus Halobatodes occur in this region. It is very desirable that those who have the opportunity should make further investigations into their life-history and habits, especially with respect to : — 1. Their food and the manner in which it is seized and retained. 2. The manner of locomotion, and especially whether all species have the power of diving. Experiments might also be made as to the effects of compulsory submergence. 3. What enemies they have, and what means of defence. 4. The use of the peculiar tubercles on the head, the perforated tubercle of the abdomen, and the ribbon-like process connected with the claws of the tarsi. The New Hebrides. On the 17th August, at noon, the island of Tongariki, one of the New Hebrides, was sighted ahead, and shortly after Makura Island on the port bow. A course was shaped to pass between Makura and Three Hills Island, the wind being a fresh trade, with numerous rain squalls. At 5.45 p.m., having cleared the channel between Makura and Three Hills Island, sail was shortened to topsails, and the vessel “ hove to ” on the port tack. The weather, being thick and rainy, was not very favourable for making observa- tions. but, so far as could be ascertained, the islands of Tongariki, Bunina, Three Hills, Makura, Two Hills, and Monument, are correctly placed relatively to each other in Admiralty chart 1380. and the positions assigned them cannot be far out. The island of Tongariki has a high solitary peak on its northeast end, while the western part is hat-topped and about 400 feet high; Bunina Island is round-backed, and about 1 F. Buchanan White, Report on the Pelagic Hemiptera, Zool. Chall. Exp., part xix., 1883. NARRATIVE OF THE CRUISE. 515 500 feet high ; Three Hills Island is readily distinguished, the peaks all being high, the middle one the lowest ; there is not much difference in their height, and the saddles between them are comparatively low. Two Hills Island has one sharp peak on its north side, the other hill is flat-topped and comparatively low, and between the two hills the island is very low, so that seen from a distance this island appears as two. The Monument is a small high rock with precipitous sides. Makura Island is wedge-shaped, “steep-to” to the southward, sloping to the northward, its summit bare, but on the northern slope are bushes and trees, and at its northwest point a small sandy beach ; the sea was seen to break against the island itself, so that it can have but a very small fringing reef, if any. Occasionally through the rain squalls a lofty peak was seen, which by its bearing must have been on the east side of Sandwich Island. Westward of Three Hills Island and Two Hills Island no bottom could be obtained at 250 fathoms. At 1.30 a.m., on the 18th, the ship wore and “ hove to” on the starboard tack. At 6 a.m. Two Hills Island bore E. ^ S., and the left peak of Three Hills Island N.E. E., and a course was shaped to pass westward of Cook’s Reef, which, however, was not seen. At 7 a.m., when Three Hills Island bore east, a course was shaped for the southwest point of Api Island, as some natives of the New Hebrides had been brought from the Fiji Islands to be landed at Api. At 8 a.m. the right extremity of Api Island bore N. 72° E., and the left extremity, the Foreland, N. by W. f W. ; from this position the ship was steered along the west coast a short distance, and at 9 a.m. sails were furled and the vessel steamed in towards the land. At this time, when the right extremity of Api bore S. 57° E., the apex of the Foreland N. 9° W., and a high hill over the coast N.E. by E., a sounding was obtained in 130 fathoms, hard ground, about 1 1 miles off the shore. Steer- ing in eastwards towards the land, soundings of 125, 95, 55, and eventually 15 fathoms were successively obtained, the latter close to a reef which fringes the point next north of the S.W. point of the island, and extends about id cables from the shore. This being the spot where the Api men wished to be landed, an armed boat was sent in to the shore as the natives were reported to be treacherous ; they proved, however, friendly enough, coming down to the beach with green branches, bows and arrows, and other weapons, so in the afternoon the officers and naturalists landed, whilst the ship dredged in the offing, there being no secure anchorage (see fig. 180). Api lies south of Ambrym and Malicolo, between these islands and Efate or Sandwich Island, and in about the same latitude as the northern part of the Fiji group. The island is upwards of 20 miles long, and its highest peak is about 1500 feet above the sea level. The island rises in steep slopes from the sea, with only here and there a stretch of fiat shore land, and consists of a series of peaks and steep-sided valleys and ridges. The whole is entirely covered with the densest possible vegetation, except on very small spots with difficulty discerned with a glass, where plots are cleared by the 516 THE VOYAGE OF H.M.S. CHALLENGER. natives for cultivation. The ship steamed close in to the island, opposite a spot where a valley terminated towards the sea with a widened mouth, evidently containing a river. There was a stretch of flat land at the bottom of the valley on which were conspicuous amongst the other foliage some cocoanut trees and another species of palm. As the vessel came near natives appeared on the shore, some hiding in the hushes, others running along at full speed, whilst some shouted a loud “ hoa.” One man stood on the shore and waved a green branch with untiring perseverance. These natives were said to be hostile and dangerous, a character which they have fully proved themselves worthy of since the visit of the Expedition, and therefore Captain N ares’ boat, the first which landed, was armed. The returned labourers, however, acted as an introduction and Fig. 189. — Landing of natives at Api, New Hebrides. made matters smooth ; still, as all the natives were armed, either with bows and poisoned arrows, clubs, or trade muskets, and as the inhabitants of these islands are noted for treachery, no one was allowed to leave the beach. Thus very little was seen of this island, which had certainly never been landed on before by any scientific man or naval officer. The shore is formed of a banked-up beach, composed of small fragments of volcanic rock and volcanic sand, mingled with a large proportion of coral fragments, and is fringed by a narrow shore platform of coral, which, near the place of landing, was not much more than 100 yards wide. This shore reef is remarkable for its extreme flatness. Almost everywhere the living corals embedded in it are growing only laterally, the upper surfaces being dead from want of sufficient depth of water. In some small specimens of NARRATIVE OF THE CRUISE. 517 a massive Porites the consequent flattening of the top and the expansion of the lateral dimensions were most excellently shown in pieces convenient for museum purposes. The corals, which were few in number as regards species, were finer grown towards the outer verge of the reef, as is always the case on shore platforms, and on the outer edge of barrier reefs. In some places were deep holes in the coral platform, reminding one of glacier crevasses on a small scale, evidently arising from the loose nature of the sloping beach on which the coral structure here rests. On the reef lay weathered remains of a more ancient shore platform which were honeycombed and wave-worn. The rock composing them was, however, undoubtedly in situ, and proved elevation of the island to the extent of five feet or so. Similar fragments of raised reef were found by Mr. Murray a short distance up the bed of the stream already mentioned. Some specimens of Porites were unattached, though living, being in the form of rounded masses entirely covered with living polyps, and probably from time to time rolled over by the waves ; an Alcyonium occurs on the coasts of England also forming rounded unattached colonies which are rolled about from place to place on the sand. They call to mind the similarly detached rounded masses formed by some Lichens ( Lecanora esculenta) which are carried about over the land by the winds as are these coral colonies by the waves. On the reefs were comparatively few free-living animals, but one of the huge Synaptce, so abundant amongst the East Indian Islands and at the Philippines, was met with. The animal was a yard long and two inches in diameter, and looked like an ugly brown and black snake. Above the shore the first land plant met with was the ubiquitous tropical littoral plant ( Ipomcea pes-caprce), which is always the first plant above high water mark on these tropical shores. Above a skirting of this commenced a thick growth of rather large trees, a species of Barringtonia, a fig, and the common Pandanus of the Pacific Islands, occupies the shore margin. A few paces within the wood it was gloomy, from the thickness of the growth of trees and creepers overhead. The same climbing Aroids grow here as at Fiji, and a Dracaena was common, as also a beautiful climbing Asclepiad (Hoy a) with white waxy flowers, and one or two ferns. The explorers were not permitted to penetrate the wood far enough to get any adequate idea of the nature of the vegetation. The Api men wore as clothing nothing but a narrow bandage of dirty European fabric of various kinds. They are a small race, few being above five feet in height, and are much darker in colour than the Fijians ; their limbs, and especially their legs, are small and badly shaped. Notwithstanding the bad character they have received, they seemed quiet enough. Several amongst those seen were returned labourers, and were at once known by their having fastened to their waist-cloth the key of the chest which every labourer brings back with him, containing the fruits of his toil, so that they thus retain, even in Api, the property for which they have worked. Two men joined the party on THE VOYAGE OF H.M.S. CHALLENGER. 518 the reef, one of whom had been in Queensland, the other in Fiji ; both spoke a good deal of English, and one said he was willing to go to Fiji again. Nearly all the men wore round their necks a small triangular ornament, cut out of one of the septa from the shell of the pearly Nautilus, and threaded by the hole through which the syphon passes. Many had broad flat tortoiseshell bracelets, and nearly all wore ear-rings made of narrow strips of tortoiseshell moulded into a flat spiral from which the tips of pigs’ tails sometimes hung as ornaments. The bows used by the natives are made of hard wood. The arrows are without feathers, but notched for the string, and made of reeds with heavy wooden ends, frequently with tips of human bone. The tips are all covered with poison, in the form of a black incrustation. The arrows have an elaborate and artistic coloured decoration in the binding round the part where the bone tips are inserted. They prize these arrows highly, and were unwilling to part with them. They carry them rolled up in an oblong strip of plantain leaf, and showed by signs that, they considered the poison deadly, and were much in awe of it. All the men have cicatrices on their bodies, usually representing a human face, and placed sometimes on the shoulder, but more often upon the breast, and sometimes on both breasts. They understood the value of the usual trade articles very well. Knives, tobacco, and pipes were what they wanted most, but they were not at all eager to trade, and few weapons or ornaments were obtained from them. The tortoiseshell bracelets they would not part with at any price. It was very trying to the scientific staff of the Expedition to be obliged to leave a totally unknown island like Api after spending only two hours on shore. Swallows ( Hirundo taliitica ) and Swifts ( Cottocalia uropygialis ) were flying about in considerable numbers near the landing place. Specimens of a Kingfisher ( Halcyon julice), a Shrike ( Artamus melaleucus ), and a Pigeon ( Carpophaga pacijica ) were also procured ; and in addition to these a Heron, Tern, and a few other birds wrere observed. A Gannet (Sula piscator ) which came on board had specimens of a Cephalopod ( Ommastrephes oualaniensis ) in its stomach. Several Spiders1 were obtained at Api: — Epeira moluccensis, Dol., Epeira man- gareva, Walck., Nephila victorialis, L. Koch, Meta sp. ?, Argyrodes sp. ?, and Trochosa sp. ?; seven species of land shells2 were collected, of which four are new: — Pythici apiensis, Melania apiensis, Melania turbans, and Melania ordinaria. The landing place was in the bay north of the first point north of the southwest extremity of the island, on a steep black sandy beach a cable south of the entrance to a small stream, and inside a large coral border, the northernmost rock above water. Whilst the officers and naturalists were on shore, some very rich hauls of the dredge 1 Determined "by Eev. 0. P. Cambridge. 2 E. A. Smith, Proc. Zool. Soc. Lond., p. 268, 1884. B i •: s-i • .f! ! -h, n/1 r ii <> Jt. : : ! v : i '• • -V . .-V. v- \ ; r . v ' . 1 '• . - \ • - ni i -■ *, - ZZ 5b; or ;« o ■- ; o 3 ■ - ■ 3 ' >■ " ; - -I ,1 3 J-i r ~i ' DIAGRAM 13 PACIFIC OCEAN Longitudinal Temperature Section . Fiji Islands to the Barrier reef , Australia For explanation of Symbols sec Appendix 1. HORIZONTAL SCALE OF NAUTICAL MILES Engraved by Mill by & Sons ] I3£0 -77*5 LKaxtdavu NARRATIVE OF THE CRUISE. 519 and trawl were obtained, in depths varying from 63 to 130 fathoms, at a distance of from half a mile to a mile from the shore. The weather was squally, rainy, and cloudy all day, so that the summit of Api Island was not visible. So far as could be distinguished, the land was intersected by numerous deep ravines and water-courses, and covered with a rich vegetation. At 4 p.m. the boats returned from the shore, and sail was made to the westward for Raine Island. Api to Raine Island and Cape York. On the 19th August, a sounding and serial temperatures were taken in 2650 fathoms. The bottom temperature here proved to be the same as that at 1300 fathoms, viz., 35° ’8. Between Australia and New Zealand, and as far north as the 25th parallel, the temperature of the wTater at the bottom was 340,5. On the 21st a sounding and serial temperatures were obtained in 2325 fathoms, the thermometer at the bottom again registering the same as those at 1300 fathoms (36° ’0). On the 24th the depth was 2450 fathoms, and the temperature observations showed results similar to those on the 21st; the same phenomenon continued for the remainder of the Stations between the New Hebrides and Raine Island, at which depths of 2440, 2275, 1700, and 1400 fathoms were obtained (see Sheet 27). The section from the Fiji Islands to Raine Island via Api Island shows that depths of 1400 fathoms exist between the Fiji and New Hebrides Islands, and of 2650 fathoms between the New Hebrides and Raine Island (see Diagram 13). The bottom shows a rapid fall from the Fijis and New Hebrides, but a very gradual rise to the Barrier Reef of Australia. The bottom temperature the whole way from the Fiji group to the Barrier Reef was uniform at about 36°, and this temperature was also found at a depth of 1300 fathoms. There exists therefore between the New Hebrides and the Barrier Reef a mass of water 1300 miles long, and 1200 fathoms in depth, of the uniform temperature of 36°. The isotherms from the surface to the depth of 1300 fathoms are very nearly parallel, the isotherm of 40° occupying a mean depth of 480 fathoms, that of 50° a mean depth of 230 fathoms, that of 60° a mean depth of 160 fathoms, and that of 70 a mean depth of 100 fathoms. There can be little doubt that the uniform temperature of the water from tlie depth of 1300 fathoms to the bottom, between the New Hebrides Islands and. Australia, is caused by the “ Coral Sea” being cut off from the colder water by an elevated ridge on the floor of the ocean over which the greatest depth of water cannot exceed 1300 fathoms. The deposits between the New Hebrides and Raine Island presented considerable variety, and were very interesting. At 2650 fathoms not a trace of carbonate of lime (narr. chall. exp. — vol. i. — 1885.) 06 520 THE VOYAGE OF H.M.S. CHALLENGER. could be detected either by the microscope, or by treating the red clay with weak acid. At 2325 fathoms there was 32 per cent, of carbonate of lime, consisting of the dead shells of pelagic Foraminifera and a few Rhabdoliths. At 2450 fathoms there was 1 or 2 per cent, of carbonate of lime, consisting of a few broken fragments of Foraminifera. At 2440 fathoms there was a red clay on the surface with only a small percentage of carbonate of lime, but three inches beneath the surface a much lighter coloured deposit containing a very large number of Foraminfera. It very frequently happened during the cruise that the deeper layers contained less car- bonate of lime than the surface ones, but only on two or three occasions were more calcareous shells noticed in the deeper layer of the deposit as in this case. The surface layer, it will be observed, was the same in nearly all respects as the deposit in 2450 fathoms 80 miles to the eastward, and the deeper layer resembled that at 2325 fathoms still farther to the eastward, or the deposits in a lesser depth towards Raine Island, which contained over 50 per cent, of carbonate of lime. It is clearly illustrated in this section, that all the other conditions remaining the same or nearly so, the quantity of carbonate of lime found in a deposit is less the greater the depth. It has been stated above that this basin below 1300 fathoms is probably cut off from the colder water farther south, and, indeed, from general oceanic circulation below that depth. In all such basins the surface shells appear to be removed from the deposits at lesser depths than in areas where there is no interruption to free communication arising from the existence of submarine barriers. The mineral particles in these deposits consisted chiefly of angular fragments of volcanic rocks and minerals, all of small size except the pieces of pumice which were numerous in all the dredgings. There were many manganese particles, and, at the sounding in 1400 fathoms, some of the Foraminifera shells were filled with the peroxide of manganese, so that a complete internal cast of the shell was left after treatment with weak acid. Amongst Ccelenterata two specimens of Umbellulci leptocaulis, Kolb, and one of Batliyactis symmetrica, Moseley, and of fishes a new genus of Opliidiidse, Typlilonus nasus, Griinth.,1 and a new species of Stomiatidse, Echiostoma microclon, Gtinth.,2 were obtained with the trawl from 2440 fathoms, together with a few other animals. Tlie Opliidiid above mentioned had a large, rounded, fleshy head ; no trace of an eye could be seen other than a small dark spot a considerable distance underneath the skin. The fins were black, but the body of the fish was white ; with the exception of one or two, all the scales had been rubbed off, and with them apparently a thin, black skin, so that probably the fish when first caught by the trawl was of a uniform black colour ; the mouth and gill chambers were black. The total length was 10 inches, depth at vent 2 inches. 1 Ann. and Ma