Aunt Lydia's-Crochet Cotton. White and Ecru: 400yd/365.75m, Solids: 350yd/320m and Shaded Colors: 300yd/274.3. Care: machine wash (max.temp. 104F/40C), dry flat, do not bleach, do not dry clean, OK to iron.
Not all colors are available everywhere, so it's nice to find what you are looking for at a fair price. Aunt Lydia's is a good brand of crochet cotton.