Complex sentence: In 1875 he became the curator of the museum's department of herpetology and he is credited for making Senckenberg's herpetological collection one of the best in Europe during his tenure there.
Split into simpler sentences: In 1875 he began work as curator of the museum's department of herpetology. Boettger is credited for making Senckenberg's herpetological collection one of the best in Europe during his tenure there.