The default symbol for excerpts shows as […]. If you wish to change this, there is are global options for you to easily control this. The options can be found in the Options > Extra > Misecellaneous tab, as seen below.
The Display Excerpt Read More Symbol option, when turned on, displays the read more symbol – […] – on excerpts throughout the site.
Under this, the Excerpt Read More Symbol option can be used to customize your preferred symbol. This field can take HTML, and if left empty, will use the default value of […].
There is also a related option under this, called Make Excerpt Symbol Link to Single Post Page. Turn this on to have the read more symbol on excerpts link to the single post page.