We have studied the production of B hadrons in 1.8-TeV <p(p)over bar> colli
sions. We present measurements of the fragmentation fractions, f(u), f(d),
f(s), and f(baryon), of produced b quarks that yield B+, B-0, B-s(0), and <
(Lambda)over bar(b)(0)> hadrons. Reconstruction of five electron-charm fina
l states yields f(s)/(f(u) + f(d)) = 0.213 +/- 0.068 and f(baryon)/(f(u) f(d)) = 0.118 +/- 0.042, assuming f(u) = f(d). If all B hadrons produced in
<p(p)over bar> collisions cascade to one of these four hadrons, we determi
ne f(u) = f(d) = 0.375 +/- 0.023, f(s) = 0.160 +/- 0.044, and f(baryon) = 0
.090 +/- 0.029. If we do not assume f(u) = f(d), we find f(d)/f(u) = 0.84 /- 0.16.