'Wilderness' signifies something with little life in it, as described in the internal sense in Luke 1:80 'Wilderness' signifies somewhere there is no good because there is no truth. 'Wilderness,' as in Jeremiah 23:10, signifies the Word when it is adulterated.

(Riferimenti: Arcana Coelestia 1927)

703. 16:14 For they are spirits of demons. This symbolically means that the lusts were lusts to falsify truths and to reason on the basis of falsities.

That demons symbolize lusts to falsify truths may be seen in no. 458 above. And because they were like frogs, the lusts were also lusts to reason on the basis of falsities, as said just above in no. 702.