Sentence:  Hatching takes 10 days; the young echidna, called a <WSD>puggle</WSD>, then sucks milk from the pores of two milk patches and remains in the pouch for 45 to 55 days, at which time the spines develop. The mother digs a nursery burrow and deposits the <WSD>puggle</WSD>, returning every 5 days to suckle it until it is weaned at 7 months. 
Meaning of the word marked with <WSD> tags:  A baby monotreme (echidna or platypus).