Sentence:  SED, both <WSD>rhotic</WSD> and nonrhotic dialects are found throughout the country. The fact that the <WSD>rhotic</WSD> dialects are relics is indicated on Map 7-5 not by the predominance of nonrhotic dialects, but by the discontinuity of the regions where <WSD>rhotic</WSD> dialects are found. A century or so earlier, they covered even more of the country, and the three regions probably formed part of a continuous network. 
Meaning of the word marked with <WSD> tags:  That allows the phoneme (/ɹ/) even when not followed by a vowel, as in "bar" ((/bɑːɹ/)) and "bard" or "barred" ((/bɑːɹd/));  who speaks with such an accent.