<div id="carousel-example-generic" class="carousel slide" data-ride="carousel">
<!-- Indicators -->
<ol class="carousel-indicators">
<li data-target="#carousel-example-generic" data-slide-to="0" class="active"></li>
<li data-target="#carousel-example-generic" data-slide-to="1"></li>
<li data-target="#carousel-example-generic" data-slide-to="2"></li>
</ol>
<!-- Wrapper for slides -->
<div class="carousel-inner" role="listbox">
<div class="item active">
<img src="1枚目の画像.jpg" class="img-responsive"
<div class="carousel-caption">
...
</div>
</div>
<div class="item">
<img src="2枚目の画像.jpg" class="img-responsive"
<div class="carousel-caption">
...
</div>
</div>
<!-- 追加する1枚分の画像ソース -->
<div class="item">
<img src="3枚目の画像.jpg" class="img-responsive"
<div class="carousel-caption">
...
</div>
</div>
<!-- ここまで追加する画像のソース -->
</div>
<!-- Controls -->
<a class="left carousel-control" href="#carousel-example-generic" role="button" data-slide="prev">
<span class="glyphicon glyphicon-chevron-left" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="right carousel-control" href="#carousel-example-generic" role="button" data-slide="next">
<span class="glyphicon glyphicon-chevron-right" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>