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 U.S. and Canada , although there are about 150 other names worldwide . 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 U.S. and Canada , although there are about 150 other synonyms worldwide .