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\begin{document}

In Exercise \#9 of Chapter 7.1.4 for the irreducible representations of
$\mathbf{Spin}(2n +1, \bbC)$, we must assume that $n \geq 3$. Note that when
$n=2$, then $\mathbf{Spin}(5, \bbC) \cong \mathbf{Sp}(4,\bC)$. With this
isomorphism, the spin representation with highest weight $\varpi_{2}$ becomes
the defining $4$-dimensional representation of $\mathbf{Sp}(4,\bC))$, whereas
the representation with highest weight $\varpi_{1}$ is the defining
$5$-dimensional representation of $\mathbf{Spin}(5, \bbC)$. 

\vspace{1ex}

\noindent
We thank  Prof. Dave Witte Morris (University of Lethbridge, CA) for pointing out this error.

\end{document}
