I think I found her in the 1850 census for Clinton County:
205BA. L. Alger30fNY
Parents would be Joseph and A. L. Alger. For some reason "A.L." reminds me of "Alvah Lee" for an Alger name. I don't know the exact lineage for this Joseph Alger. The unique name "Serril" (Cyrel above) has been passed around awhile. My guess is that Joseph Alger is a son of Oliver Alger - a Clinton County pioneer. Oliver Alger was born Feb. 15, 1788 and I have no other info on him other than seeing his name mentioned in a Clinton County history book (and, of course, the Family Bible).