diff --git a/src/tracker/array.jl b/src/tracker/array.jl
index d23062d4..89bd05e4 100644
--- a/src/tracker/array.jl
+++ b/src/tracker/array.jl
@@ -199,7 +199,7 @@ end
 # NNlib
 
 using NNlib
-import NNlib: softmax, ∇softmax, logsoftmax, ∇logsoftmax, logσ, ∇logσ, conv2d, pool
+import NNlib: softmax, ∇softmax, logsoftmax, ∇logsoftmax, conv2d, pool
 
 softmax(xs::TrackedArray) = track(softmax, xs)
 
@@ -209,10 +209,6 @@ logsoftmax(xs::TrackedArray) = track(logsoftmax, xs)
 
 back(::typeof(logsoftmax), Δ, xs) = @back(xs, ∇logsoftmax(Δ, data(xs)))
 
-logσ(xs::TrackedArray) = TrackedArray(Call(logσ, xs))
-
-back(::typeof(logσ), Δ, xs) = @back(xs, ∇logσ(Δ, data(xs)))
-
 # TODO: can store kwargs efficiently in namedtuples
 _conv2d(x, w, stride, pad) = conv2d(x, w, stride = stride, padding = pad)