Complex sentence: The Fox terrier and Jack Russell terrier type dogs of today are all descended from dogs of that period, although documented pedigrees earlier than 1862 have not been found, although several records remain of documented breeding by John Russell between the 1860s and 1880s.
Split into simpler sentences: The Fox terrier and Jack Russell terrier type dogs of today are all descended from dogs of that period, although documented pedigrees earlier than 1862 have not been found. Several records remain of documented breeding by John Russell between the 1860s and 1880s.