תרגום - צרפתית-אנגלית - De Jussieu dans son interprétation est...

The meaning is:
DeJussieu's interpretations (of a text?) are stricter (more au pied de la lettre) than his colleagues', but basically his ideas accord with theirs.
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The word "exclusif" seems to imply he is not as "loose" (or "broad" ) in his interpretation as his colleagues.

That was what I've thought, Ian. De Jussieu doesn't accept as many propositions as his colleagues do (the same meaning "exclusivo" has in Portuguese).