TY - JOUR T1 - Studies in Heredity. I.-The Effects of Crossing the Sea-urchins Echinus esculentus and Echinocardium cordatum JF - Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character (1905-1934) VL - 84 IS - 573 SP - 394 EP - 403 PY - 1911/12/28/ UR - http://dx.doi.org/10.1098/rspb.1911.0085 M3 - doi:10.1098/rspb.1911.0085 AU - MacBride, E. ER -