Richard F. Burton relates that according to R. Jeremiah Bin Eliazar in Psalm XLI.5, Adam was excommunicated for one hundred and thirty years during which he begat children in his own image (Gen. V.3) and these were Mazikeen or Shedeem - Jinns. Muslims considered the Jinn or Djinn a supernatural anthropoid being, created of subtle fire (Koran Surahs, XV.27; LV.14), not of earth like man, propagating his kind, ruled by mighty kings, the last being Jan bin Jan, missionarised by Prophets and subject to death and Judgement.
Of course we now know this all to be false superstition. The common Genie that infests the Snail Factory is in fact a fungus. Similar to Grosmannia Clavigera, genies are a form of Ascomycota or "Sac Fungus", more specifically they are its sentient spores.
While Ile St. Paul had a few naturally growing Genies before the factory, the dark, dank and foetid corners of the Factory's deep labyrinthine sprawl provided an ideal setting for the Djinn to prosper. By the early 40s, the fungal wish beasts had organized their own storage zones and bunkers within the factory walls and instituted a constitutional monarchy. The true extent of the infestation was nearly twice as thick as the survey in this episode suggests.
The brief tenting and spraying ordered by Dr. Breign was thus ineffectual, killing off some of the fruiting bodies but none of the spores, in part due to the underestimation and in part due to Efengi, who missed the memo and got stuck in the tented towers. Seeing several Djinn running for cover, he lent a hand to assist and made complete the failure of the ill-conceived degeniezation.