sentences:  Unaware of their origin, Bartlett named the pears after himself and introduced the variety into the United States.It was not realised that Bartlett and Williams Pears were the same until 1828, when new trees arrived from Europe.By that time the Bartlett variety had become vastly popular in the United States, and they are still generally known as Bartlett pears in the US and Canada, although there are about 150 other synonyms worldwide.