Interesting. I have in hand a SOM Berthiot brochure from around 1950. It lists Flor enlarging lenses: 50/3.5, 75/4.5, 105/4.5, 135/4.5, 165/4.5 and 200/4.5. And it shows pictures of some of them.
It also mentions Flor taking lenses, shows pictures of 105/3.5 and 300/4.5, both in barrel.
The two types' barrels differ. The OP's lens looks like a taking lens, not like an enlarging lens. In fact, it looks much like my 135/6.8 Perigraphe Ser. VIb in barrel. I vote for taking lens.
I also have images of some pages of an SOM Berthiot catalog from around 1950. It lists a 165/4.5 Flor taking lens, for 10 cm x 15 cm. I vote for taking lens.
jp498, reasoning from one manufacturer to another rarely works well. Also, that a lens is in barrel doesn't mean that it has to be an enlarging lens. This is a typical ignorant ebay seller's mistake, and is how I once snagged a 135/5.6 Symmar in barrel for $32 delivered.