Editing caption size of thebibliography environment

Question

I was wondering if it is possible to change the size of the caption generated by the thebibliography environment. Changing the actual text size can be accomplished by putting thebibliography environment between \begin{small} \end{small} (or whatever textsize is needed), but that doesn't seem to affect the caption.

\documentclass[12pt]{article}
\usepackage[T1]{fontenc} 
\usepackage[utf8]{inputenc}
\usepackage[german,german]{babel}
\addto\captionsgerman{\renewcommand{\refname}{Referenzen}}
\renewcommand{\refname}{Referenzen}

\usepackage[justification=justified,singlelinecheck=false]{caption}
\renewcommand{\arraystretch}{1.5}
\usepackage{ulem}
\usepackage[labelfont=bf,textfont=footnotesize]{caption}

\begin{document}

\begin{footnotesize}

\begin{thebibliography}{5}
    \bibitem{Hon89} Honig, M. G. and Hume, R. I. {\em Dil and diO: versatile fluorescent dyes for neuronal labelling and pathway tracing} Trends in Neuroscience 12, Nr.9 (1989):333-5,340-1.
    \bibitem{WoAmPh} {\em Nervous system, neuronal support cells}. \url{http://wormatlas.org/hermaphrodite/neuronalsupport/jump.html?newLink=mainframe.htm&newAnchor=Phasmidsensilla36}. Access: 31.12.17, 11:59.
\end{thebibliography}

\end{footnotesize}

\end{document}

With \addto\captionsgerman{\renewcommand{\refname}{Referenzen}} and \renewcommand{\refname}{Referenzen}, I was able to change the caption text, but I'm not sure how to change the fontsize. Thanks in advance!

Answer 1

I guess that your aim is to have the bibliography section in smaller type. Adding footnotesize and changing manually the size for the title is not the solution.

\documentclass[12pt]{article}
\usepackage[T1]{fontenc} 
\usepackage[utf8]{inputenc}
\usepackage[ngerman]{babel}
\usepackage{caption}
\usepackage{url}
\usepackage{etoolbox}

\captionsetup{
  justification=justified,
  singlelinecheck=false,
  labelfont=bf,
  textfont=footnotesize,
}
\addto\captionsngerman{\renewcommand{\refname}{Referenzen}}
\apptocmd{\thebibliography}{\footnotesize}{}{} % bibliography in footnote size
\patchcmd{\thebibliography}{\refname}{\normalsize\refname}{}{}

%\renewcommand{\arraystretch}{1.5}% <--- ???

\begin{document}

\section*{A section}

Some text to see what happens with the bibliography.

\begin{thebibliography}{5}

\bibitem{Hon89}
Honig, M. G. and Hume, R. I. \emph{Dil and diO: versatile fluorescent 
  dyes for neuronal labelling and pathway tracing}.
  Trends in Neuroscience 12, Nr.9 (1989):333-5,340-1.

\bibitem{WoAmPh}
\emph{Nervous system, neuronal support cells}. 
\url{http://wormatlas.org/hermaphrodite/neuronalsupport/jump.html?newLink=mainframe.htm&newAnchor=Phasmidsensilla36}. Access: 31.12.17, 11:59.

\end{thebibliography}

\end{document}

Some notes.

1. I removed the underlining: it's a don't-do-it in good typography
2. Bibliography items should be followed by a blank line
3. Loading caption twice is not the best way to specify multiple options
4. I used ngerman (Neue Rechtschreibung) instead of german
5. I commented out the setting to \arraystretch, not understanding what it's supposed to do

With a further patch one can remove the vertical space between bibliography items.

\documentclass[12pt]{article}
\usepackage[T1]{fontenc} 
\usepackage[utf8]{inputenc}
\usepackage[ngerman]{babel}
\usepackage{caption}
\usepackage{url}
\usepackage{etoolbox}

\captionsetup{
  justification=justified,
  singlelinecheck=false,
  labelfont=bf,
  textfont=footnotesize,
}
\addto\captionsngerman{\renewcommand{\refname}{Referenzen}}
\apptocmd{\thebibliography}{\footnotesize}{}{} % bibliography in footnote size
\patchcmd{\thebibliography}{\refname}{\normalsize\refname}{}{}
\patchcmd{\thebibliography}
  {\leftmargin}
  {\setlength{\itemsep}{0pt}\setlength{\parsep}{0pt}\leftmargin}
  {}{}

%\renewcommand{\arraystretch}{1.5}% <--- ???

\begin{document}

\section*{A section}

Some text to see what happens with the bibliography.

\begin{thebibliography}{5}

\bibitem{Hon89}
Honig, M. G. and Hume, R. I. \emph{Dil and diO: versatile fluorescent 
  dyes for neuronal labelling and pathway tracing}.
  Trends in Neuroscience 12, Nr.9 (1989):333-5,340-1.

\bibitem{WoAmPh}
\emph{Nervous system, neuronal support cells}. 
\url{http://wormatlas.org/hermaphrodite/neuronalsupport/jump.html?newLink=mainframe.htm&newAnchor=Phasmidsensilla36}. Access: 31.12.17, 11:59.

\end{thebibliography}

\end{document}

Answer 2

You can do it by adding the desired font size to the macro that redefines \refname like below:

\addto\captionsgerman{\renewcommand{\refname}{\fontsize{40}{46}\selectfont Referenzen}}