TY - JOUR T1 - The Skeleton and Classification of Calcareous Sponges JF - Proceedings of the Royal Society of London (1854-1905) VL - 64 SP - 61 EP - 76 PY - 1898/01/01/ UR - http://dx.doi.org/10.1098/rspl.1898.0070 M3 - doi:10.1098/rspl.1898.0070 AU - Bidder, G. ER -