The present study reports three species of Farrea Bowerbank, 1862 from Campos Basin (southwestern Atlantic): Farrea herdendorfi Duplessis and Reiswig, 2004, Farrea occa Bowerbank, 1862, and Farrea campossinus sp. nov. This is the first record of F. herdendorfi for the South Atlantic and only the second record of the species worldwide. Farrea occa is described and reported to form mass occurrences in the area's sponge and coral banks, as seen in extensive video recording undertaken between 900 and 1100 m depth. The new species approaches Farrea foliascens Topsent, 1906 very closely, but differs in that its hooked anchorate clavules are much larger and the meshes of its dictyonal framework rather more irregular. Our thoughts on whether the proposed new species deserved species or subspecies rank led to an investigation on the usage of subspecies rank in Porifera. A historical overview, mainly contrasting Demospongiae and Hexactinellida is offered here. We concluded that no rule of thumb is readily made out from the comparative analysis of various authors' taxonomic decisions. Until one such agreement is achieved, it appears to us that naming new subspecies should be objectively argued for, or better, totally avoided, as a useless further dimension to taxonomic uncertainty in poriferan classification.

Sponges are regarded as the most primitive of animals because of their 'simple' body plans, having a multicellular grade of construction but without actual tissues or organs, yet studies of this oldest of metazoan groups have contributed a great deal to our understanding of life on Earth. For example, the discovery of complex immune and cell-aggregation systems in sponges has led to better understanding of the cellular processes of higher organisms and, in particular, the nature of cell surfaces as active agents in cell and tissue recognition (Bergquist 1994). Their fossil record dates back about 600 million years (Finks 1970; Li et al. 1998).

Two new species of Farrea and a single new species of a closely related new genus, Asceptrulum, all members of the hexactinosan family Farreidae, are described from three widely distant locations. Farrea herdendorfi, new species, with a type series of eight specimens obtained from 2200 m off Charleston, South Carolina, U.S.A., NW Atlantic Ocean, is distinguished by two anchorate clavule forms (umbellate and thimblate or thimble-shaped), both without spiral arrangement of claws. Farrea seiri, new species, represented by 3 fragments of a single specimen from 1450 m near the South East Indian Ridge, mid Indian Ocean, is characterized by only anchorate clavules of thimblate form, a moderate proportion of which have claws spiralled. Asceptrulum axialis, new genus, new species, is represented by several fragments from a single specimen collected from 2387 m on the Juan de Fuca Ridge, northern Oregon, U.S.A., NE Pacific Ocean. It is distinguished by the combination of complete absence of sceptrules and a one-layered farreoid framework. The diagnosis of Farreidae is emended to encompass the new genus.

Two new species of Farrea and a single new species of a closely related new genus, Asceptrulum, all members of the hexactinosan family Farreidae, are described from three widely distant locations. Farrea herdendorfi, new species, with a type series of eight specimens obtained from 2200 m off Charleston, South Carolina, U.S.A., NW Atlantic Ocean, is distinguished by two anchorate clavule forms (umbellate and thimblate or thimble-shaped), both without spiral arrangement of claws. Farrea seiri, new species, represented by 3 fragments of a single specimen from 1450 m near the South East Indian Ridge, mid Indian Ocean, is characterized by only anchorate clavules of thimblate form, a moderate proportion of which have claws spiralled. Asceptrulum axialis, new genus, new species, is represented by several fragments from a single specimen collected from 2387 m on the Juan de Fuca Ridge, northern Oregon, U.S.A., NE Pacific Ocean. It is distinguished by the combination of complete absence of sceptrules and a one-layered farreoid framework. The diagnosis of Farreidae is emended to encompass the new genus.

Glass sponges are enigmatic members of the deep-sea fauna that inhabit shallow waters in only a few locations world-wide. In order to understand what factors influence the distribution of glass sponges, patterns of distribution and abundance of reef and non-reef forming hexactinellids in fjords of British Columbia, Canada, were analyzed from photographs and transcripts recorded on dives undertaken by the 'Pisces IV' manned submersible during the 1980s. Hexactinellids are widely distributed throughout all fjords from 16 to 650 m depths, and in some fjords abundances reach 240 individuals in 10 m(2). In all fjords hexactinellids were most abundant at depths of 20 to 260 m, even where water depths exceeded 500 m. Glass sponges were rare in regions of inlets where oxygen levels fall below 2 ml l(-1), or in areas of high sediment deposition. Highest abundances coincided with water conditions of high dissolved silicate, low light, temperatures between 9 and 10degreesC and low suspended sediments. Extensive glass sponge skeletons in the inner basin of Howe Sound reflect past stress in this fjord that may include oxygen deficit, sediment loading from a mine and contamination from industrial sites. The observations from 'Pisces IV' suggest that glass sponges may be sentinel species for current and past seawater conditions in coastal British Columbia.

Heterotella pomponae, a new species, is reported from near S. Caicos Is., West Indies. This is only the second described species of the genus and the first from the Atlantic Basin. Heterotella was erected by Gray to accommodate Alcyoncellum corbicula Bowerbank from Isle de Bourbon (Reunion), southwest Indian Ocean. The genus is distinguished from other Corbitellinae by a microsclere which has controversial interpretation, as either a oxyhexactin with long spines or an oxyhexaster with irregularly originating terminal rays. The two species are distinguished by presence of sigmatocomes in H. pomponae and their absence in H. corbicula.

A new species, Sycon escanabensis Duplessis & Reiswig, is de­ scribed from material retrieved by submersible from 3500 m depth in the Esca­ naba Trough, central Gorda Ridge, off northern California. The species differs from all other members of the genus by the combination of conspicuous tripar­ tite body organization and slender, lancet-head diactins that ornament the ex­ ternal surface and the oscular margin. This is the first deep-water (> 1000 m) calcareous sponge described from the North Pacific Basin. MEMBERS OF THE PORIFERAN class Calcarea

In thin sections of resin-embedded samples of glutaraldehyde- and osmium tetroxide-fixed tissue from five genera of marine sponges, Stromatospongia, Astrosclera, Jaspis, Pseudoceratina and Axinyssa, cells of a bacteria-like symbiont microorganism which exhibit a membrane-bounded nuclear region encompassing the fibrillar nucleoid have been observed within the sponge mesohyl. The nuclear region in these cells is bounded by a single bilayer membrane, so that the cell cytoplasm is divided into two distinct regions. The cell wall consists of subunits analogous to those in walls of some Archaea. Cells of the sponge symbionts observed here are similar to those of the archaeal sponge symbiont Cenarchaeum symbiosum.

Summary The order Verongida, considered to be exclusively oviparous and dioecious, exhibits great range in body form, including thin-bodied, rope- and stick-form members which have been postulated to be morphologically adapted to exploit fragmentation as an important asexual reproductive process. Here we report results of a one-year survey of sexual reproductive stages in a rope-form verongid, Aplysina cauliformis, which test the hypotheses of verongiid sexual pattern and reduced resource allocation to sexual reproduction in rope-form sponges. Results confurn the verongiid pattern of oviparity, dioeciousness and production of small oocytes. Data also support the hypothesis that rope-form sponges are characterized by reduced investment in gamete production relative to sponges of other body forms. The sexual reproductive pattern of the main macrosymbiont (parasite) polychaete, Haplosyllis spongicola, shows no correlation to that of its sponge host.

A new genus and species, Leioplegma polyphyllon, of the hexactinellid family Aulocalycidae is described from nearly undamaged fragments collected by submersible from the ship-wreck of the S.S. CENTRAL AMERICA. Proposed re-diagnosis of the family stresses as its basic feature the formation of primary dictyonal strands from single hexactin rays and returns this group to Ijima's original concept.

The freshwater Bryozoa (Ectoprocta) are one of the most poorly known faunal groups in Canada. A recent survey of 80 freshwater habitats in eastern Canada (from Ontario to Newfoundland) revealed 14 species of bryozoans, representing 56% of described species in North America. The greatest numbers of species and specimens were found in alkaline waters (pH 7.0–9.8) near lake outflows, wherever hard substrates were present. Paludicella articulata, Cristatella mucedo, Fredericella indica, and Plumatella fungosa are among the most frequently encountered, widely distributed, and eurytopic species. Pottsiella erecta and Plumatella fruticosa are rare, and new to eastern Canada. Lophopodella carteri, an exotic Asian species discovered in Lake Erie in the early 1930s, has become firmly established in the lower Ottawa and upper St. Lawrence rivers. Detailed notes on taxonomy, morphology, distribution, and ecology are given for each bryozoan. New limits of tolerance to water temperature, pH, and calcium and magnesium hardness are established for several species. A taxonomic key to the freshwater bryozoans of eastern Canada, including a key to statoblast types, is presented for the first time.

During a recent survey of the freshwater sponges of eastern Canada (from Ontario to Newfoundland), 15 species were recorded, representing approximately 50% of the total number of species known from North America. Radiospongilla crateriformis, Spongilla aspinosa, and Trochospongilla horrida are reported from Canada for the first time. Two problematic species, Corvosporigilla novaeterrae and Spongilla johanseni, are reviewed and their status is revised. Detailed notes on taxonomy, morphology, distribution, and ecology are given. New limits of tolerance with respect to pH, water temperature, and calcium and magnesium concentrations are established for several species. A taxonomic key to the freshwater sponges of eastern Canada is presented.

Larval behaviour, settlement, and metamorphosis were investigated in four Caribbean commercial sponges, Hippospongia lachne, Spongia barbara, S. cheiris and S. graminea, using light and transmission electron microscopy. The parenchymella larvae of these viviparous and gonochoristic species have an average size of 350-mu-m by 420-mu-m when released. Symbiotic bacteria occur intercellularly in both larvae and post-larvae. Laboratory behavioural studies demonstrate that free-swimming larvae display directional swimming with constant lateral rotation and negative phototaxis. Larval settlement occurs 26-56 hours after release from the parent and involves the formation of a basal lamella between the post-larva and substrate. There is no evidence of larval substrate selection by type or orientation. The canal system begins to form six days after settlement and oscules are apparent eleven days post-settlement. Available evidence suggests that larval ciliated epithelial cells are terminally differentiated and do not appear to contribute to formation of post larva or adult in this group of Porifera.

Sexual reproductive cycles of a Florida, U.S.A., population of four Caribbean commercial sponge species, Hippospongia lachne, Spongia barbara, S. cheiris and S. graminea, were determined by analysis of tissue samples collected over a three-year period. Spermatogenesis in these species was studied using light and transmission electron microscopy. The production of male gametes occurs in cysts within the endosomal tissue of mature specimens. Reproductive elements within an individual cyst develop synchronously while development between cysts is asynchronous. All available evidence suggests that these species are dioecious. Spermatogonia differentiate directly from choanocytes in situ. All cells of the chamber lose their collars and flagella and undergo mitosis to produce primary spermatocytes, each possessing a single flagellum. The ratio of nucleus to cell diameter in these cells is almost double that of choanocytes. Circumstantial evidence suggests that primary spermatocytes undergo meiosis to produce four spermatids, but confirmational chromatid linkage figures are still lacking. The mature spermatozoa lack both intermediate segments and acrosomes. Male gametes displayed a bright yellow-white autofluorescence when excited with blue light (460-485 nm).