diff --git a/src/PkgDeps.jl b/src/PkgDeps.jl
index cc2255f..aa7fed7 100644
--- a/src/PkgDeps.jl
+++ b/src/PkgDeps.jl
@@ -154,14 +154,14 @@ function direct_dependencies(pkg_entry::PkgEntry)
 end
 
 function direct_dependencies(pkg_name::String; registries::Array{RegistryInstance}=reachable_registries())
-    if pkg_name in keys(STDLIBS)
+    if pkg_name in values(STDLIBS)
         return Dict{String, UUID}()
     end
     return direct_dependencies(_find_latest_pkg_entry(pkg_name, missing; registries))
 end
 
 function direct_dependencies(pkg_uuid::UUID; registries::Array{RegistryInstance}=reachable_registries())
-    if pkg_uuid in values(STDLIBS)
+    if pkg_uuid in keys(STDLIBS)
         return Dict{String, UUID}()
     end
     return direct_dependencies(_find_latest_pkg_entry(missing, pkg_uuid; registries))
diff --git a/test/runtests.jl b/test/runtests.jl
index cc7e3cc..d317002 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -136,6 +136,12 @@ end
     deps = direct_dependencies("Case2"; registries=all_registries)
     @test deps == Dict("DownDep" => UUID("000eeb74-f857-587a-a816-be5685e97e75"),
                        "Statistics" => UUID("10745b16-79ce-11e8-11f9-7d13ad32a3b2"))
+
+    deps = direct_dependencies("LinearAlgebra")
+    @test isempty(deps)
+    # test with LinearAlgebra's UUID
+    deps = direct_dependencies(UUID("37e2e46d-f89d-539d-b4ee-838fcccc9c8e"))
+    @test isempty(deps)
 end
 
 @testset "`dependencies`" begin