Styling for <select> is missing
See http://foundation.zurb.com/sites/docs/v/5.5.3/components/forms.html.
Something like this should do it:
select {
-webkit-appearance: none !important;
-moz-appearance: none !important;
background-color: #FAFAFA;
border-radius: 0;
background-image: url("data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZlcnNpb249IjEuMSIgeD0iMTJweCIgeT0iMHB4IiB3aWR0aD0iMjRweCIgaGVpZ2h0PSIzcHgiIHZpZXdCb3g9IjAgMCA2IDMiIGVuYWJsZS1iYWNrZ3JvdW5kPSJuZXcgMCAwIDYgMyIgeG1sOnNwYWNlPSJwcmVzZXJ2ZSI+PHBvbHlnb24gcG9pbnRzPSI1Ljk5MiwwIDIuOTkyLDMgLTAuMDA4LDAgIi8+PC9zdmc+");
background-position: 100% center;
background-repeat: no-repeat;
border-style: solid;
border-width: 1px;
border-color: #cccccc;
color: #444444;
font-family: inherit;
font-size: 0.77778rem;
line-height: normal;
padding: 0.44444rem;
border-radius: 0;
height: 2.05556rem;
}