Sentence:  Lawrence E . Griffin gives measurements of nineteen young anacondas , presumably <WSD>members</WSD> of a brood , from `` South America '' ; the extreme measurements of these fall between the lower limit of the Brookfield brood and its average . 
Meaning of the word marked with <WSD> tags:  one of the persons who compose a social group (especially individuals who have joined and participate in a group organization)