SILURIAN HEXACTINELLID SPONGES FROM NORTHERN BRITISH-COLUMBIA, CANADA

Faunules of largely hexactinellid sponges have been collected from sil tstones of Early Silurian Wenlock or latest Landovery age within the u pper Road River Group from northern British Columbia. The assemblages include the new species: Protospongia columbiana Hexatractiella pseudo nevadensis and Crathophycus akiensis. Other taxa described include the hexactinellids Protospongia conica Rigby and Harris, 1979, Hexatracti ella nevadensis (Rigby and Stuart, 1988), Diagoniella sp., Gabelia ped unculus? Rigby and Murphy, 1983, and a specimen of the monaxonid demos ponge Wareiella typicala Rigby and Harris, 1979. Also included is a fr agment of what must have been a steeply obconical-cylindrical hexactin ellid sponge of uncertain taxonomy; it has a skeleton of robust hexact ines in an unquadruled net, above a root-tuft of 10-20 spicules. Other sponge impressions include small circular clusters of hexactines with radiating, to basketlike patterns and somewhat similar, isolated and dissociated, long probably roof tuft spicules and possible basal root tuft rosettes of monaxons. The faunules are similar to other outer con tinental margin, black shale, sponge assemblages of the Early Paleozoi c Era, and include elements previously described from northern British Columbia and central Nevada.