Sentence:  There are three messages which can be sent by means of the convolvulus. A white one <WSD>signifies</WSD> "Why are you fleeing me?" A pink one <WSD>signifies</WSD> "I shall bind myself to you". A blue one <WSD>signifies</WSD> "I shall wait for better days". 
Meaning of the word marked with <WSD> tags:  To mean; to betoken.