REGION OF WEEDS EQUIVALENT TO THE LAMINARIAN REGION OF THE EUROPEAN SEAS.
Some seventeen or eighteen localities in this Bathymetrical province were explored by means of the dredge, varying in depth from one to seventeen fathoms. In the south-east Australian province the principal Gasteropoda procured were Bulla brevis, at Port Jackson, in 6 fathoms; Cyprea oryza, at Port Phillip, in 5 fathoms; Calyptraea connata, in 6 fathoms, Port Jackson, with Nassa suturalis, and another, a new Terebra, Monotigma casta, Mitra sordida, a Marginella, a Columbella, and Struthiolaria oblita. A Phasianella was dredged in from 3 to 5 fathoms on sandy mud, at Port Phillip, with Elenchus rutilus, Marginella fornicata, and Cerithium granarium. In the North-east Australian province, a different set of shells was dredged in similar depths, such as a Sigaretus, possibly new, Fissurella calyculata, Mitra obeliscus, a Turritella, a Murex, Columbella versicolor, and a new species off Cape York, Ranella pulchella, new, several Nassae, Phos senticosa and blainvillei, and sculptilis, in 3 and 5 fathoms, off Cape York; Strombus campbelli, in mud off Cape Upstart; Cerithium obeliscus, and a new species of the genus Obeliscus. In the deeper localities Cypraea fimbriata occurred, dead, off Cape Capricorn; and two species of Ranella, one being R. pusilla, in 17 fathoms, off the Percy Isles. The univalves dredged among the Louisiade Islands in this region of depth were mostly known forms, such as Conus betulinus, Oliva sanguinolenta, Mitra exasperata, Terebra maculata, consors and labiata; these were all taken in less than six fathoms water.
The bivalves of this region were but few. In the South Australian province species of Mactra, Psammobia, Venus, Tapes and Pecten, all peculiar, were taken. This is the region of the peculiar genus Myadora, of which five species were dredged on sand in 6 fathoms at Port Jackson, along with Myochama anomioides, Trigonia margaritacea, Lima bullata, and Cardium radiatum. In the North-east Australian province we have species of Donax, Mactra and Corbula, all apparently new, from the shallower localities; Corbula tunicata, Pectunculus tenuicostatus, and another, from 8 to 11 fathoms, off Cumberland Islands; species of Arca, Pectunculus, Avicula, Pecten, Venus, Circe, Cardium, Cardita, and Erycina, mostly new, from 15 to 17 fathoms in a sandy and shelly bottom off Cape Capricorn.
CORALLINE ZONE.
Some dredgings in both North and South-eastern provinces, in depths between twenty-seven and forty-five fathoms, give a slight idea of the fauna of this important region. In the South-eastern province we find in forty and forty-five fathoms on a muddy bottom in Bass Strait, Turritella sinuata, Trochus nebulosus, a Pleurotoma, an Emarginula, a Dentalium, two species of Cardita, a Cypricardia, a Venus, a Nucula, and Pectunculus holosericeus. In the North-eastern province we find off Cumberland Island in 27 fathoms, also on a muddy bottom, species of Murex, Nassa, Turritella, Ranella pusilla, a Fusus, Cancellaria antiquata, a Terebra, two Dentalia, a Natica, a Terebellum, a Scalaria, a Cardium, a Venus, a Nucula, a Pecten, and a Spondylus.
It is evident from the comparative paucity of undescribed species procured in the Littoral zone and the large proportion of new or doubtful forms among those taken by the dredge, that a rich harvest has yet to be reaped in the deeper regions of the southern seas. In the lower zones, however, just as much as in the upper, the distinctions of province are maintained. The explanation of this complete separation of the South-eastern marine fauna of Australia from that of the North-eastern or Indo-Pacific portion, may be explained by reference to the distribution of currents along the Australian shores. In both, as in the Bathymetrical regions of the South Atlantic, the Testacea of the depths are generally smaller and less brightly coloured than those inhabiting the shallows.
During this voyage notes of the habitats of considerably more than a thousand species of Mollusca and Echinodermata were carefully registered.
2. ENUMERATION OF TERRESTRIAL PULMONIFEROUS MOLLUSCA AS YET NOTICED IN AUSTRALIA.
The following Catalogue is founded on the monograph of Helicidae by Dr. Pfeiffer. To the species therein described are added certain new ones, announced by Pfeiffer since the publication of his work, and others, recorded for the first time in this volume. It will be seen that a great part of the Australian land-shells is as yet unfigured. The exact localities of not a few have to be determined; a precise record was kept of the place and circumstances under with each was found during the voyage of the Rattlesnake. From all we yet know the genus Helix is fairly represented in New Holland, and presents some very remarkable and peculiar forms; Bulimus has but few, and those (with the sole exception of B. atomatus) not remarkable Australian members; a single Pupa, closely resembling one of our commonest European species, is the only recorded Australian one; and a very remarkable addition to the terrestrial conchology of the southern hemisphere has been made in a Balea of a type unlike any other member of the genus.
HELIX.