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Nucleon and $\Delta$ resonances in the fourth resonance region are studied ina multichannel partial-wave analysis which includes nearly all available dataon pion- and photo-induced reactions off protons. In the high-mass range, above1850\,MeV, several alternative solutions yield a good description of the data.For these solutions, masses, widths, pole residues and photo-couplings aregiven. In particular, we find evidence for nucleon resonances withspin-parities $J^P=1/2^+...7/2^+$. For one set of solutions, there are fourresonances forming naturally a spin-quartet of resonances with orbital angularmomentum L=2 and spin S=3/2 coupling to $J=1/2,...,7/2$. Just below 1.9\,GeV wefind a spin doublet of resonances with $J^P=1/2^-$ and $3/2^-$. Since a spinpartner with $J^P=5/2^-$ is missing at this mass, the two resonances form aspin doublet which must have a symmetric orbital-angular-momentum wave functionwith L=1. For another set of solutions, the four positive-parity resonances areaccompanied by mass-degenerate negative-parity partners -- as suggested by theconjecture of chiral symmetry restoration. The possibility of a $J^P=1/2^+,3/2^+$ spin doublet at 1900\,MeV belonging to a 20-plet is discussed.

Nucleon resonances in the fourth resonance region