Calbraith Perry chose to not use the final "e" of Bourne as commonly used. He was not the bishop of the family but his nephew James DeWolf Perry who was bishop Rhode Island and from 1930-1937 the Presiding Bishop of the Episcopal Church. I have both the Perry book you mentioned (just recently purchased) and a copy of Julia Bourne Thuber's Grandfather's Grandparents which traces Calbraith's Perry's brothers forbears. I have copied it out and can send you a file if you are interested. Also there is a Bourne Genealogy by Lee, Helen Bourne Joy, Pequot Press, Chester, CT, 1972.