Studies of the top quark at the Tevatron

We report on studies of the top quark, beyond the measurements of its mass and produciton cross section, which have been carried out recently by the CDF and D0 collaborations, based on {approximately}110{+-}6 pb{sup -1} of proton-antiproton collisions at a center-of-mass energy of 1.8 TeV. Each experiment has searched for t{yields}H{sup +}b decays and, from the lack of observable signal, excluded previously unexplored regions of the [M{sub H+},tan{beta}] parameter space. D0 has studied the correlation between the spin states of pair-produced top quarks, and CDF has studied the helicity of the W bosons produced in the decay of top quarks. Within large statistical uncertainties, both measurements agree with predictions of the standard model