  We continue our program of describing hadrons as rotating strings with
massive endpoints. In this paper we propose models of baryons and confront them
with the baryon Regge trajectories. We show that these are best fitted by a
model of a single string with a quark at one endpoint and a diquark at the
other. This model is preferred over the Y-shaped string model with a quark at
each endpoint. We show how the model follows from a stringy model of the
holographic baryon which includes a baryonic vertex connected with N_c strings
to flavor probe branes. From fitting to baryonic data we find that there is no
clear evidence for a non-zero baryonic vertex mass, but if there is such a mass
it should be located at one of the string endpoints. The available baryon
trajectories in the angular momentum plane (J,M^2), involving light, strange,
and charmed baryons, are rather well fitted when adding masses to the string
endpoints, with a single universal slope of 0.95 GeV^-2. Most of the results
for the quark masses are then found to be consistent with the results extracted
from the meson spectra in a preceding paper, where the value of the slope
emerging from the meson fits was found to be 0.90 GeV^-2. In the plane of
quantum radial excitations, (n,M^2), we also find a good agreement between the
meson and baryon slopes. The flavor structure of the diquark is examined, where
our interest lies in particular on baryons composed of more than one quark
heavier than the u and d quarks. For these baryons we present a method of
checking the holographic interpretation of our results.
