Sentence:  Anatomically , the horse <WSD>lung</WSD> appears to be remarkably like that of man , insofar as this can be ascertained from comparison of our findings in the horse with those of others ( Birnbaum , ' 54 ) in the human being . 
Meaning of the word marked with <WSD> tags:  either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood